JP7119168B2 - Drum unit, cartridge, electrophotographic image forming apparatus and coupling member - Google Patents

Description

The present invention relates to an electrophotographic image forming apparatus using an electrophotographic method, and a drum unit, cartridge, coupling member and the like used therein.

In an electrophotographic image forming apparatus, there is known a configuration in which elements such as a photosensitive drum and a developing roller, which are rotating bodies involved in image formation, are integrated as a cartridge and detachable from the main body of the image forming apparatus (hereinafter referred to as the apparatus main body). ing. In such a configuration, many apparatuses employ a configuration in which a driving force is received from the apparatus main body in order to rotate the photosensitive drum in the cartridge. At that time, there is known a configuration in which a coupling member on the cartridge side is engaged with a driving force transmission portion such as a drive pin on the apparatus main body side to transmit the driving force.

For example, Japanese Unexamined Patent Application Publication No. 2008-233867 discloses a cartridge having a coupling member provided at the end of a photoreceptor drum so as to be tiltable with respect to the rotation axis of the photoreceptor drum.

It is to develop the above-mentioned prior art.

A typical configuration is
in the drum unit
a photoreceptor drum;
A coupling member capable of transmitting a driving force toward the photosensitive drum, comprising: (i) a main body having a cylindrical shape ; (ii) a projection movable with respect to the main body; and (iii) the projection. (iv) a second extension connected to the inner surface of said body; and (v) said first extension between said first and second extensions. a coupling member having a connecting portion connecting the portion and the second extending portion;
has
The first extension is connected to the main body via the second extension,
A first direction in which the first extension portion extends from the connection portion and a second direction in which the second extension portion extends toward the connection portion are opposite to each other in an axial direction of the coupling member,
The protrusion is a drum unit that protrudes from the first extending portion so as to approach the axis of the coupling member.
Another typical configuration is
in the cartridge,
a rotating body configured to carry toner on its outer peripheral surface;
A coupling member capable of transmitting a driving force toward the rotating body, comprising: (i) a body having a cylindrical shape ; (ii) a projection movable with respect to the body; and (iii) supporting the projection. (iv) a second extension connected to the inner surface of the body; and (v) the first extension between the first extension and the second extension. and a connection portion connecting the second extension portion;
has
The first extension is connected to the main body via the second extension,
A first direction in which the first extension portion extends from the connection portion and a second direction in which the second extension portion extends toward the connection portion are opposite to each other in an axial direction of the coupling member,
The protrusion is a cartridge that protrudes from the first extending portion so as to approach the axis of the coupling member.

The above prior art has been developed.

1 is a schematic cross-sectional view of an image forming apparatus 100; FIG. 3 is an external perspective view of a drum cartridge 13; FIG. 3 is an external perspective view of a developing cartridge 4; FIG. 3 is a cross-sectional view of a virtual plane including the rotation center of the photosensitive drum 1 of the drum cartridge 13. FIG. It is an outline drawing of a main body drive shaft. FIG. 3 is a cross-sectional view cut at the center of the rotation axis (the center of the rotation axis) of the main body drive shaft 101 attached to the main body of the image forming apparatus. 3 is a cross-sectional view of a drum cartridge 13 and a developing cartridge 4; FIG. 3 is a cross-sectional view of the coupling 28 and the main body drive shaft 101 cut along the rotation axis (rotational axis); FIG. 4 is a cross-sectional view of the coupling member 28 and the main body drive shaft 101 cut in a direction perpendicular to the rotation axis; FIG. FIG. 3 is a cross-sectional view of the coupling 28 and the main body drive shaft 101 cut along the rotation axis; 4 is a perspective view of a flange member 70; FIG. It is the figure which looked at the flange member 70 from the Z1 side to the Z2 side. 3 is a cross-sectional perspective view of a flange member 70; FIG. 4 is a cross-sectional view of the flange member 70 taken along the center of the rotation axis (the center of the rotation axis); FIG. 7 is a cross-sectional view of the coupling member 28 and the main body drive shaft 101 cut in a direction perpendicular to the rotation axis so as to pass through the drive transmission surface 73a. FIG. 4 is a cross-sectional view of the coupling member 28 taken along the center of the rotation axis (the center of the rotation axis); FIG. FIG. 5 is an explanatory cross-sectional view for explaining a molding die for the flange member 70; 3 is a perspective view of an alignment member 33; FIG. 4A and 4B are diagrams for explaining a method of assembling the coupling member 28; FIG. FIG. 3 is a perspective view for explaining how the drum cartridge 13 is attached to the image forming apparatus main body 100A; FIG. 5 is a cross-sectional view for explaining the mounting operation of the drum cartridge 13 to the image forming apparatus main body 100A; FIG. 5 is a cross-sectional view for explaining the mounting operation of the coupling member 28 to the main body drive shaft 101; The coupling member 28 is attached to the main body drive shaft 101 when the main body drive shaft 101 rotates from a state where the main body drive transmission groove 101a and the engaging portion 73 (the drive receiving surface 73a) are out of phase and the phases match. FIG. 4 is a cross-sectional view for explaining the operation; 5 is a cross-sectional view for explaining an operation of removing the coupling member 28 from the main body drive shaft 101; FIG. FIG. 11 is a cross-sectional view of a coupling member 128 according to Example 2 taken along the center of the rotation axis (the center of the rotation axis); FIG. 11 is a cross-sectional view of a coupling member 128 and a main body drive shaft 101 according to Embodiment 2 cut along a direction perpendicular to the rotation axis at a position passing through a drive receiving surface 73a; FIG. 10 is a view of a flange member 170 according to Example 2 as seen from the outside in the Z direction, and a cross-sectional view; FIG. 10 is a side view and a side view of an inner cylindrical member 140 according to Example 2 as viewed from the Z1 side to the Z2 side; FIG. 11 is an explanatory cross-sectional view showing the assembly procedure of the coupling member 128 according to the second embodiment; FIG. 10 is a view of the assembly procedure of the coupling member 128 according to the second embodiment, viewed from the outside in the Z direction and from the side; FIG. 11 is a cross-sectional view of the flange member 270 according to Example 3 taken along the center of the rotation axis (the center of the rotation axis); FIG. 11 is a cross-sectional view of a coupling member 228 and a main body drive shaft 101 according to Embodiment 3 cut at a position passing through a support portion 74 in a direction perpendicular to the rotation axis; FIG. 11 is a perspective view of an alignment member 233 according to Example 3; FIG. 13 is a diagram showing another form of the coupling member 228 according to the third embodiment; FIG. 11 is a cross-sectional view of a coupling member 328 according to Embodiment 4 cut along the center of the rotation axis (the center of the rotation axis); FIG. 13A is a view of a flange member 370 according to a fourth embodiment as seen from the outside in the Z direction, and a cross-sectional view thereof; FIG. 14 is a perspective view of an inner cylindrical member 340 according to Example 4; FIG. 11 is a perspective view of an alignment member 333 according to Example 4; FIG. 12 is an explanatory diagram of assembly of the coupling member 328 according to the fourth embodiment; FIG. 11 is a cross-sectional view of a coupling member 328 and a main body drive shaft 101 according to Embodiment 4 cut at a position passing through a drive transmission surface 373a in a direction perpendicular to the rotation axis; FIG. 14 is a diagram showing another embodiment of the inner cylindrical member 340 according to Example 4; FIG. 11 is an outline view of a main body drive shaft 5101 according to Example 5; FIG. 12 is a cross-sectional view taken along a rotation axis (rotational axis) of the main body drive shaft 5101 in a state where the main body drive shaft 5101 according to the fifth embodiment is attached to the main body of the image forming apparatus; FIG. 11 is a cross-sectional view of a coupling member 528 according to Example 5 taken along the rotation axis; FIG. 14 is a cross-sectional view of a cylinder member 570 cut along the rotation axis according to the fifth embodiment; FIG. 11 is a cross-sectional view of a coupling member 528 and a main body drive shaft 5101 according to Embodiment 5 cut along a direction perpendicular to the rotation axis of the coupling member 528 so as to pass through a drive receiving surface 573a; FIG. 11 is a perspective view of an alignment member 533 according to Example 5; FIG. 11 is a diagram illustrating assembly of a coupling member 528 according to Example 5; FIG. 12 is a cross-sectional view of the developing cartridge 4 according to Example 5, taken along the axis of the toner supply roller 20 and the developing roller 17; FIG. 12 is a perspective view for explaining how the developing cartridge 4 according to the fifth embodiment is attached to the image forming apparatus main body 100A; FIG. 12 is a cross-sectional view for explaining the mounting operation of the developing cartridge 4 according to Embodiment 5 to the image forming apparatus main body 100A; FIG. 21 is a cross-sectional view for explaining the mounting operation of the coupling member 528 according to the fifth embodiment to the main body drive shaft 5101; FIG. 14 is a diagram showing another embodiment of the cylinder member 570 according to Example 5; FIG. 14 is a diagram showing another embodiment of the cylinder member 570 according to Example 5; FIG. 12 is a diagram showing another embodiment of the coupling member 528 according to Example 5; FIG. 14 is a diagram showing another embodiment of the cylinder member 570 according to Example 5; FIG. 12 is a diagram showing another embodiment of the coupling member 528 according to Example 5; FIG. 21 is a perspective view of an alignment member 633 according to Example 6; FIG. 11 is a cross-sectional view of an alignment member 633 according to Example 6 cut along the rotation axis; FIG. 11 is a cross-sectional view of a coupling member 628 according to Embodiment 6 and cut along a drive receiving surface 673a in a direction perpendicular to the rotation axis; FIG. 21 is a perspective view of a cylinder member 670 according to Example 6; FIG. 11 is a cross-sectional view of a coupling member 628 according to Embodiment 6 taken along the rotation axis; FIG. 11 is a diagram for explaining assembly of a coupling member 628 according to Embodiment 6; FIG. 10 is a diagram showing a modification of Example 1; FIG. 10 is a diagram showing a modification of Example 1;

An image forming apparatus, a drum cartridge, and a developing cartridge of this embodiment will be described below with reference to the drawings. The image forming apparatus forms an image on a recording medium using, for example, an electrophotographic image forming process. Examples include electrophotographic copiers, electrophotographic printers (eg, LED printers, laser beam printers, etc.), electrophotographic facsimile machines, and the like. Further, the cartridge is detachable from the main body of the image forming apparatus (apparatus main body, image forming apparatus main body, electrophotographic image forming apparatus main body). In particular, a drum cartridge is a cartridge having a photosensitive drum. A developing cartridge is a cartridge having developing means for developing a latent image formed on a photoreceptor. In this embodiment, each of the drum cartridge and the developing cartridge is detachable from the main body of the image forming apparatus. Also, a unit in which the photosensitive drum, the coupling member and the like are integrated is called a drum unit. Drum units are used in drum cartridges.

Note that the following embodiment exemplifies a full-color image forming apparatus in which four drum cartridges and four developing cartridges are attachable and detachable. However, the number of drum cartridges and developer cartridges to be mounted on the image forming apparatus is not limited to this. In addition, in the embodiments, a configuration using two types of cartridges, a drum cartridge and a developing cartridge, is exemplified, but the present invention is not limited to this. For example, a cartridge having a structure such as a process cartridge that integrates the functions of a drum cartridge and a developing cartridge may be used. Likewise, the materials, arrangement, dimensions, and other numerical values of each configuration disclosed in the examples are not limited unless otherwise specified. Further, unless otherwise specified, the upper side indicates the upper side in the direction of gravity when the image forming apparatus is installed.

<Example 1>
[Overview of Electrophotographic Image Forming Apparatus]
First, the overall configuration of an electrophotographic image forming apparatus (image forming apparatus) according to the present embodiment will be described with reference to FIG.

FIG. 1 is a schematic cross-sectional view of an image forming apparatus 100 of this embodiment.

As shown in FIG. 1, an image forming apparatus 100 has a plurality of image forming units, which are first, first, and second image forming units for forming yellow (Y), magenta (M), cyan (C), and black (K) images, respectively. It has second, third and fourth image forming units SY, SM, SC and SK. In this embodiment, the first to fourth image forming units SY, SM, SC, and SK are arranged in a line substantially horizontally.

In this embodiment, the configuration and operation of the drum cartridges 13 (13Y, 13M, 13C, 13K) and the developing cartridges 4 (4Y, 4M, 4C, 4K) are substantially the same except that the colors of the formed images are different. essentially the same. Therefore, hereinafter, Y, M, C, and K will be omitted and a general description will be given unless a particular distinction is required.

In this embodiment, the image forming apparatus 100 has, as a plurality of image carriers, cylinders (hereinafter referred to as photoreceptor drums) 1 having four photosensitive layers arranged side by side in a direction slightly inclined with respect to the vertical direction. . A scanner unit (exposure device) 3 is arranged below the drum cartridge 13 in the direction of gravity. Further, around the photosensitive drum 1, a charging roller 2 and the like are arranged as process means (process device, process member) acting on the photosensitive layer.

The charging roller 2 is charging means (charging device, charging member) that uniformly charges the surface of the photosensitive drum 1 . A scanner unit (exposure device) 3 is exposure means (exposure device, exposure member) that forms an electrostatic image (electrostatic latent image) on the photosensitive drum 1 by irradiating a laser based on image information. A developing cartridge 4 and a cleaning blade 6 as cleaning means (cleaning device, cleaning member) are arranged around the photosensitive drum 1 .

Further, an intermediate transfer belt 5 as an intermediate transfer member for transferring the toner images on the photosensitive drums 1 onto a recording material (sheet, recording medium) 12 is arranged so as to face the four photosensitive drums 1 . there is

The developing cartridge 4 of this embodiment uses a non-magnetic one-component developer (hereinafter referred to as "toner") as a developer, and employs a contact development method in which a developing roller 17 as a developer carrying member is brought into contact with the photosensitive drum 1. We are hiring.

In the above configuration, the toner image formed on the photosensitive drum 1 is transferred onto a sheet (paper) 12, and the toner image transferred onto the sheet is fixed. As process means acting on the photosensitive drum 1, the drum cartridge 13 includes a charging roller 2 that charges the photosensitive drum 1, a cleaning blade 6 that cleans toner remaining on the photosensitive drum 1 without being transferred, Prepare. Untransferred toner remaining on the photosensitive drum 1 without being transferred onto the sheet 12 is collected by the cleaning blade 6 . Further, the transfer residual toner collected by the cleaning blade 6 is stored in the removed developer storage section (hereinafter referred to as waste toner storage section) 14a through the opening 14b (see FIG. 7). The waste toner container 14a (see FIG. 7) and the cleaning blade 6 are integrated to form a cleaning unit (photoreceptor unit, image carrier unit) 13. As shown in FIG.

Further, the image forming apparatus 100A includes guides (positioning means) such as a mounting guide and a positioning member (not shown) on the main body frame. The developing cartridge 4 and the drum cartridge 13 are guided by the guides described above, and are detachable from the image forming apparatus main body 100A.

The toners of yellow (Y), magenta (M), cyan (C), and black (K) are accommodated in the developer cartridges 4 for the respective colors.

The intermediate transfer belt 5 contacts the photosensitive drum 1 provided in each process cartridge and rotates (moves) in the direction of arrow B in FIG. The intermediate transfer belt 5 is stretched over a plurality of supporting members (driving roller 51, secondary transfer counter roller 52, driven roller 53). Four primary transfer rollers 8 as primary transfer means are arranged side by side on the inner peripheral surface side of the intermediate transfer belt 5 so as to face each photosensitive drum 1 . A secondary transfer roller 9 as a secondary transfer means is arranged at a position facing the secondary transfer facing roller 52 on the outer peripheral surface side of the intermediate transfer belt 5 .

When forming an image, first, the surface of the photosensitive drum 1 is uniformly charged by the charging roller 2 . Next, the charged surface of the photoreceptor drum 1 is scanned and exposed by laser light emitted from the scanner unit 3 according to image information. As a result, an electrostatic latent image corresponding to image information is formed on the photosensitive drum 1 . The electrostatic latent image formed on the photosensitive drum 1 is developed as a toner image (developer image) by the developing roller 17 (see FIG. 3) of the developing cartridge 4 . The toner image formed on the photosensitive drum 1 is transferred (primary transfer) onto the intermediate transfer belt 5 by the action of the primary transfer roller 8 .

For example, when forming a full-color image, the above-described process is sequentially performed in the four drum cartridges 13 (13Y, 13M, 13C, 13K) and developer cartridges 4 (4Y, 4M, 4C, 4K). Then, toner images of respective colors formed on the photosensitive drums 1 of the drum cartridges 13 are sequentially primary-transferred so as to be superimposed on the intermediate transfer belt 5 . After that, the recording material 12 is conveyed to the secondary transfer portion in synchronization with the movement of the intermediate transfer belt 5 . Then, the four-color toner image on the intermediate transfer belt 5 is collectively transferred onto the recording material 12 conveyed to the secondary transfer portion formed by the intermediate transfer belt 5 and the secondary transfer roller 9 .

The recording material 12 onto which the toner image has been transferred is conveyed to a fixing device 10 as fixing means. A toner image is fixed on the recording material 12 by applying heat and pressure to the recording material 12 in the fixing device 10 . Further, primary transfer residual toner remaining on the photosensitive drum 1 after the primary transfer process is removed by the cleaning blade 6 and collected as waste toner. Secondary transfer residual toner remaining on the intermediate transfer belt 5 after the secondary transfer process is removed by the intermediate transfer belt cleaning device 11 .

Note that the image forming apparatus 100 is also capable of forming monochromatic or multicolor images using a desired single or some (not all) image forming units.

[Outline of process means]
Next, an outline of the drum cartridge 13 and the developing cartridge 4 mounted in the image forming apparatus main body 100A of this embodiment will be described with reference to FIGS. 2, 3, 4 and 7. FIG.

The drum cartridge 13Y, the drum cartridge 13M, the drum cartridge 13C, and the drum cartridge 13K have the same configuration. Further, the developing cartridge 4Y containing yellow toner, the developing cartridge 4M containing magenta toner, the developing cartridge 4C containing cyan toner, and the developing cartridge 4K containing black toner have the same configuration. . Accordingly, in the following description, the drum cartridges 13Y, 13M, 13C, and 13K are collectively referred to as the drum cartridge 13, and the developing cartridges 4Y, 4M, 4C, and 4K are collectively referred to as the developing cartridge 4. Each cartridge constituent member will also be generically described in the same way.

FIG. 2 is an external perspective view of the drum cartridge 13. As shown in FIG. Here, as shown in FIG. 2, the rotation axis direction of the photosensitive drum 1 is the Z direction (arrows Z1 and Z2), the horizontal direction in FIG. 1 is the X direction (arrows X1 and X2), and the vertical direction in FIG. is the Y direction (arrow Y1, arrow Y2).

The drum cartridge 13 has a cleaning frame 14 as a frame that supports various elements inside the drum cartridge 13 . The photosensitive drum 1 is rotatably supported by the cleaning frame 14 .

The photosensitive drum 1 is a rotating body (image carrier) configured to carry an image (toner image, developer image) formed with toner (developer) on its surface.

FIG. 4 is a cross-sectional view of a virtual plane including the rotation center of the photosensitive drum 1 of the drum cartridge 13. As shown in FIG. The side of the photosensitive drum 1 in which the coupling member 28 receives the driving force from the main body of the image forming apparatus (side in the Z1 direction) is called the drive side (back side) of the drum cartridge 13 . The side opposite to the driving side in the axial direction (side in the Z2 direction) is called the non-driving side (front side) of the drum cartridge 13 .

When the drum cartridge 13 is attached to the apparatus main body, the driving side of the drum cartridge 13 is arranged downstream in the cartridge mounting direction, and the non-driving side is arranged upstream in the mounting direction. In other words, when the drum cartridge 13 is arranged inside the main body of the apparatus, the driving side of the drum cartridge 13 is arranged on the back side of the printer, and the non-driving side of the drum cartridge 13 is arranged on the front side of the printer. placed.

The axial direction of the photoreceptor drum 1 is a direction parallel to the axis (rotational axis) of the photoreceptor drum 1 . The axis of the photoreceptor drum 1 is an imaginary straight line passing through the center of rotation of the photoreceptor drum 1, and corresponds to the dashed line passing through the center of the photoreceptor drum 1 in FIG. At the end opposite to the coupling member 28 (the non-driving end of the process cartridge), there is an electrode (electrode portion) that contacts the inner surface of the photosensitive drum 1, and this electrode contacts the main body of the image forming apparatus. By doing so, it plays a role of earth.

A coupling member 28 is attached to one end of the photoreceptor drum 1 and a non-driving side flange member 29 is attached to the other end of the photoreceptor drum 1 to form a photoreceptor drum unit (simply called a drum unit) 30 . The photosensitive drum unit 30 receives driving force from a main body drive shaft 101 provided in the image forming apparatus main body 100A through the coupling member 28 .

The coupling member 28 is a flange member (driving side flange member) attached to the driving side end of the photosensitive drum 1 . The coupling member 28 can be engaged with the main body drive shaft 101 when the cartridge 7 is attached to the apparatus main body 100A. Further, the coupling member 28 can be separated from the main body drive shaft 101 as the cartridge 7 is removed from the apparatus main body 100A.

The photosensitive drum 1, the coupling member 28, and the non-drive side flange member 29 provided in the drum unit 30 are coaxially arranged. These rotational axes (axes) coincide with the rotational axis of the drum unit 30 . Therefore, the axis and the direction of the axis of the drum unit 30 are the same as the axis and the direction of the axis of the photosensitive drum 1, the coupling member 28 and the non-drive side flange member 29, respectively.

As shown in FIG. 4, the Z1 side of the coupling member 28 has a cylindrical shape (cylindrical portion 71). A portion on the Z1 side of the cylindrical portion 71 serves as a bearing portion 71c. The bearing portion 71c is rotatably supported by the drum unit bearing member 39R. That is, the photosensitive drum unit 30 becomes rotatable by supporting the bearing portion 71c by the bearing portion of the drum unit bearing member 39R.

Similarly, the non-driving side flange member 29 provided on the non-driving side of the photosensitive drum unit 30 is rotatably supported by the bearing portion of the drum unit bearing member 39L. The non-driving side flange member 29 has a cylindrical portion (cylindrical portion) protruding from the end portion of the photosensitive drum 1, and the outer peripheral surface 29a of this cylindrical portion is rotatably supported by the drum unit bearing member 39L. The outer peripheral surface 29a is a bearing portion on the non-drive side.

The drum unit bearing member 39R is arranged on the driving side of the drum cartridge 13, and the drum unit bearing member 39L is arranged on the non-driving side of the drum cartridge 13. As shown in FIG.

When the drum cartridge 13 is attached to the apparatus main body 100A, as shown in FIG. 4, the drum unit bearing member 39R abuts against the inner cartridge positioning portion 108 provided in the image forming apparatus main body 100A. Also, the drum unit bearing member 39L abuts against the front side cartridge positioning portion 110 of the image forming apparatus main body 100A. Thereby, the cartridge 7 is positioned in the image forming apparatus 100A.

In the Z direction of this embodiment, the position where the drum unit bearing member 39R supports the bearing receiving portion 71c is arranged close to the position where the drum unit bearing member 39R is positioned by the inner cartridge positioning portion . By doing so, it is possible to prevent the coupling member 28 from tilting when the drum cartridge 13 is attached to the apparatus main assembly 100A.

The bearing portion 71c is arranged so that the position where the bearing member 39R supports the bearing portion 71c and the position where the bearing member 39R is positioned by the rear cartridge positioning portion 108 are brought closer. That is, the bearing portion 71c is arranged on the front end side (Z1 direction side) of the outer peripheral surface 71a of the cylindrical portion 71 provided in the coupling member .

Similarly, in the Z direction, the drum unit bearing member 39L rotatably supports the non-driving side flange member 29 is located near the position where the drum unit bearing member 39L is positioned by the front side cartridge positioning portion 110. . This prevents the non-driving side flange member 29 from tilting. or 1
Drum unit bearing members 39R and 39L are attached to both sides of the cleaning frame 14, respectively, and support the photosensitive drum unit 30, respectively. As a result, the photosensitive drum unit 30 is rotatably supported by the cleaning frame 14 .

Also, the charging roller 2 and the cleaning blade 6 are attached to the cleaning frame 14 and are arranged so as to contact the surface of the photosensitive drum 1 . Also, the charging roller bearings 15 (15R, 15L) (see FIG. 7) are attached to the cleaning frame 14 . The charging roller bearing 15 is a bearing for supporting the shaft of the charging roller 2 .

FIG. 7 is a sectional view of the drum cartridge 13 and the developing cartridge 4. As shown in FIG.

Here, the charging roller bearing 15 (15R, 15L) is attached so as to be movable in the direction of arrow C shown in FIG. A rotating shaft 2a of the charging roller 2 is rotatably attached to charging roller bearings 15 (15R, 15L). The charging roller bearing 15 is urged toward the photosensitive drum 1 by a pressure spring 16 as urging means. As a result, the charging roller 2 abuts against the photosensitive drum 1 and rotates following the photosensitive drum 1 .

The cleaning frame 14 is provided with a cleaning blade 6 as cleaning means for removing toner remaining on the surface of the photosensitive drum 1 . The cleaning blade 6 is formed by integrating a blade-shaped rubber (elastic member) 6a that contacts the photosensitive drum 1 to remove the toner on the photosensitive drum 1 and a supporting metal plate 6b that supports it. In this embodiment, the support plate 6b is fixed to the cleaning frame 14 with screws.

As described above, the cleaning frame 14 has the opening 14 b for collecting the transfer residual toner collected by the cleaning blade 6 . The opening 14b is provided with a blowout prevention sheet 26 that abuts against the photosensitive drum 1 and seals the space between the photosensitive drum 1 and the opening 14b, thereby preventing toner leakage upward from the opening 14b.

3 is an external perspective view of the developing cartridge 4. FIG.

The developing cartridge 4 has a developing frame 18 that supports various elements. The developing cartridge 4 is provided with a developing roller 17 as a developer carrying member that contacts the photosensitive drum 1 and rotates in the direction of arrow D (counterclockwise) shown in FIG. The developing roller 17 is a rotating body (developing member) for carrying developer on its surface to be supplied to the photosensitive drum 1 . The latent image on the photosensitive drum 1 is developed by the toner supplied from the developing roller 17 to the photosensitive drum 1 .

The developing roller 17 is rotatably supported by the developing frame 18 via developing bearings 19 (19R, 19L) at both ends in its longitudinal direction (rotational axis direction). Here, the developing device bearings 19 (19R, 19L) are attached to both sides of the developing device frame 18, respectively.

7, the developer cartridge 4 has a developer storage chamber (hereinafter referred to as a toner storage chamber) 18a and a development chamber 18b in which the development roller 17 is arranged.

In the developing chamber 18b, there are provided a toner supply roller 20 as a developer supplying member that contacts the developing roller 17 and rotates in the direction of arrow E, and a developing blade as a developer regulating member for regulating the toner layer of the developing roller 17. 21 are arranged.

The supply roller (supply member) 20 is also a rotating member that carries developer (toner) on its surface and rotates, and is a developer carrying member like the developing roller. The toner carried on the surface of the supply roller 20 is supplied to the developing roller 17 .

The developing blade 21 is fixed and integrated with the fixing member 22 by welding or the like.

Further, in the toner storage chamber 18 a of the developing frame 18 , an agitating member 23 for agitating the stored toner and conveying the toner to the toner supply roller 20 is provided.

Employment of such a configuration in which elements related to image formation are integrated into the drum cartridge 13 and the developing cartridge 4 that are detachably attachable to the main body of the apparatus improves ease of maintenance. In other words, the user can easily perform maintenance of the apparatus by attaching and detaching the drum cartridge 13 and the developing cartridge 4 to and from the apparatus main body 100A. Therefore, it is possible to provide an apparatus that can be easily maintained not only by service personnel but also by users.

In this embodiment, the drum cartridge 13 and the developing cartridge 4 are installed in the main body A of the apparatus independently of each other. However, the drum cartridge 13 and the developing cartridge 4, which are used to form images of the same color, may be integrated into one unit. It is also possible to adopt a configuration in which the unitized cartridge (process cartridge) is detachable from the apparatus main body. [Configuration of main body drive shaft]
5, 6, 8, 9, and 10, the configuration of the main body drive shaft 101 will be described.

FIG. 5 is an outline drawing of the main body drive shaft.

FIG. 6 is a sectional view cut along the rotation axis (rotational axis) of the main body drive shaft 101 attached to the main body of the image forming apparatus.

FIG. 8 is a cross-sectional view of the coupling 28 and the main body drive shaft 101 cut along the rotation axis (rotational axis).

FIG. 9 is a cross-sectional view of the coupling member 28 and the main body drive shaft 101 cut in a direction perpendicular to the rotation axis.

FIG. 10 is a cross-sectional view of the coupling 28 and main body drive shaft 101 taken along the axis of rotation.

As shown in FIG. 5, the main body drive shaft 101 has a gear portion 101e, a shaft portion 101f, a rough guide portion 101g, and a bearing portion 101d.

The image forming apparatus main body 100A is provided with a motor (not shown) as a drive source. The motor rotates the gear portion 101e to rotate the main body drive shaft 101. As shown in FIG. Further, the main body drive shaft 101 has a rotatable projection-shaped shaft portion 101f that projects toward the cartridge side from the gear portion 101e along the rotation axis. The rotational driving force received from the motor is transferred to the photosensitive drum 1 of the drum cartridge 13 via the groove-shaped drive transmission groove 101a (recessed portion, drive transfer portion) provided in the shaft portion 101f and the coupling member 28. is transmitted. Moreover, the shaft portion 101f has a hemispherical shape 101c at its tip.

The main body drive transmission groove 101a is shaped so that a part of an engaging portion 73, which will be described later, can enter. Specifically, it includes a main body drive transmission surface 101b as a surface that contacts the drive receiving surface (drive receiving portion) 73a of the coupling member 28 and transmits the driving force.

Further, as shown in FIG. 5, the main body drive transmission surface 101b is not flat, but has a twisted shape around the rotation axis of the main body drive shaft 101. As shown in FIG. The twist direction is a direction in which the Z1 direction side of the main body drive shaft 101 is disposed on the upstream side in the rotation direction of the main body drive shaft 101 with respect to the Z2 direction side. In this embodiment, the amount of twisting of the engaging portion 73 along the direction of the axis of rotation of the cylinder is about 1° per 1 mm. The reason why the body drive transmission surface 101b has a twisted shape will be described later.

In addition, a body-side withdrawal taper 101i is provided on the surface of the body drive transmission groove 101a on the Z2 direction side. The body-side withdrawal taper 101i is a taper (inclined surface, inclined portion) for helping the engaging portion 73 to come out of the drive transmission groove 101a when the drum cartridge 13 is removed from the apparatus main body 100A. Details will be described later.

Here, when the drive is transmitted from the drive transmission groove 101a to the engaging portion 73, it is desirable that the main body drive transmission surface 101b and the drive receiving surface (drive receiving portion) 73a are brought into contact with each other. Therefore, the main body drive transmission groove 101a is arranged in the rotation axis direction, the circumferential direction, and the radial direction so that the surfaces other than the main body drive transmission surface 101b do not come into contact with the engaging portion 73 as the driving force receiving portion. A configuration having a gap (G) with respect to 73 is adopted (see FIGS. 9 and 10).

In addition, a body-side extraction taper 101i as an inclined surface (inclined portion) is provided on the tip side in the axial direction of the main body drive transmission groove 101a. Further, in the axial direction of the main body drive shaft 101, the center 101h of the hemispherical shape 101c is arranged within the range of the main body drive transmission groove 101a (see FIG. 8). In other words, when the center 101h and the main body drive transmission groove 101a are projected onto the axis of the main body drive shaft 101, the projected area of the center 101h is arranged inside the projected area of the main body drive transmission groove 101a on the axis.

The rough guide portion 101g is provided between the shaft portion 101f and the gear portion 101e in the axial direction (see FIG. 6). The rough guide portion 101g has a tapered tip on the shaft portion 101f side, and the outer diameter D6 of the rough guide portion 101g, as shown in FIG. smaller than the inner diameter D2 of 71b. Further, the outer diameter D6 of the rough guide portion 101g is larger than the outer diameter D5 of the shaft portion 101f, as shown in FIG. As a result, when the cartridge 7 is inserted into the image forming apparatus main body 100A, the main body drive shaft 101 is connected to the coupling member 28 so as to reduce misalignment between the rotation center of the cylindrical portion 71 and the rotation center of the shaft portion 101f. I can guide you to learn. Therefore, the rough guide portion 101g can be rephrased as an insertion guide.

It should be noted that the rough guide portion 101g is set to have a dimensional relationship such that it does not come into contact with the inner peripheral surface 71b after the cartridge 7 is completely attached to the image forming apparatus main body 100A.

As shown in FIG. 6, the bearing receiving portion 101d is arranged on the opposite side of the rough guide portion 101g across the gear portion 101e. The bearing portion 101d is rotatably supported (rotated) by a bearing member 102 provided in the image forming apparatus main body 100A.

Further, as shown in FIG. 6, the body drive shaft 101 is biased against the drum cartridge 13 by a spring member 103 of the image forming apparatus body 100A. However, the movable amount (backlash) of the main body drive shaft 101 in the Z direction is about 1 mm, which is sufficiently smaller than the width in the Z direction of the drive receiving surface 73a described later.

As described above, the main body drive shaft 101 is provided with the main body drive transmission groove 101a, and the coupling member 28 is provided with the engaging portion 73 to transmit the drive from the apparatus main body 100A to the drum cartridge 13 (drum unit 30).

Although the details will be described later, the engaging portion 73 is provided at the tip of a support portion 74 that is elastically deformable. Therefore, the engaging portion 73 is configured to be movable radially outward when the drum cartridge 13 is attached to the apparatus main body 100A. Accordingly, as the drum cartridge 13 is inserted into the apparatus main body 100A, the engaging portion 73 enters the drive transmission groove 101a, and the engaging portion 73 can be engaged with the body drive transmission groove 101a.

[Configuration of Coupling Member]
The structure of the coupling member 28 will be described with reference to FIGS. 11 to 19. FIG.

11 is a perspective view of the flange member 70. FIG. 12 is a view of the flange member 70 viewed from the Z1 side to the Z2 side. FIG. 13 is a cross-sectional perspective view of the flange member 70. FIG. 14 is a flange member. FIG. 15 is a cross-sectional view of 70 taken along the center of the rotation axis (the center of the rotation axis), and FIG. FIG. 16 is a cross-sectional view of the coupling member 28 cut at the center of the rotation axis (the center of the rotation axis). FIG. 19A and 19B are perspective views of the alignment member 33. FIG. 19 is a view explaining a method of assembling the coupling member 28. The coupling member 28, as shown in FIG. Become.

(Description on flange member)
The configuration of the flange member 70 will be described with reference to FIGS.

The flange member 70 includes an attachment portion (fixed portion) 72, a cylindrical portion 71, a collar portion 75, an engaging portion 73, a support portion 74, and a force receiving portion 77, as shown in FIG.

The attachment portion 72 is a portion for attachment to the photosensitive drum 1 . As shown in FIG. 11, the mounting portion 72 includes a press-fitting portion 72d that is press-fitted into the inner diameter of the cylinder of the photoreceptor drum 1, a caulking groove 72e, and a press-fitting groove 72e provided on the far side (Z2 direction side) of the press-fitting portion 72d. It has a guide portion 72f.

The press-fit portion 72 d as a coupling portion is a portion for fixing the coupling member 28 to the photoreceptor drum 1 by being press-fitted into the photoreceptor drum 1 . Specifically, the inner diameter of the cylinder of the photoreceptor drum 1 and the outer shape of the press-fitting portion 72d are so dimensioned as to have an interference fit relationship. It should be noted that the above relationship is not limited to a configuration that increases the fastening force due to caulking or a case where the inner diameter of the cylinder and the press-fitting portion 72d are fixed by adhesion.

As shown in FIGS. 11 and 12, the caulking groove 72e has a groove shape (recess) provided on the photosensitive drum 1 side of the press-fit portion 72d in the Z-axis direction. Two caulking grooves 72e are evenly arranged around the rotational axis of the coupling member 28. As shown in FIG. In addition, in the rotation axis direction of the coupling member 28, the caulking groove 72e and the flange portion 75 are arranged so as to overlap each other. In other words, when the crimping groove 72e and the collar portion 75 are projected perpendicularly to the rotational axis of the coupling member 28, the projected area of the crimping groove 72e and the projected area of the collar portion 75 overlap on the axis. .

Note that "in the A direction, X and Y overlap (overlap)" means that "when X and Y are projected onto a virtual line parallel to the A direction, the projection of X on the virtual line At least part of the area overlaps with at least part of the projected area of Y." By crimping a portion of the end of the photoreceptor drum 1 on the side of the coupling member 28, the photoreceptor drum 1 is plastically deformed. As a result, a part of the photoreceptor is inserted into the caulking groove 72e, and the photoreceptor drum 1 and the coupling member 28 are firmly fixed. Note that crimping refers to an operation of plastically working and joining a part of a plurality of parts. In this embodiment, the cylinder (aluminum) of the photosensitive drum 1 is coupled to the coupling member 28 by partially plastically deforming the cylinder (aluminum) of the photosensitive drum 1 . In this embodiment, as an example of a means for firmly fixing the coupling member 28 to the photosensitive drum 1, the crimping groove 72e is used. Alternative fixing means can also be used. Therefore, the caulking groove 72e is not an essential component.

The press-fitting guide portion 72f facilitates the assembly of the coupling member 28 to the photoreceptor drum 1 when the coupling member 28 is assembled to the photoreceptor drum 1, and stably press-fits the press-fitting portion 72d to the photoreceptor drum 1. is the shape of Specifically, the outer diameter of the press-fitting guide portion 72f is smaller than the outer diameter of the press-fitting portion 72d and the inner diameter of the cylinder of the photosensitive drum 1, and has a guide taper 72g on the leading end side in the mounting direction to the photosensitive drum 1. The guide taper 72g is an inclined portion provided on the coupling member 28 to facilitate insertion of the coupling member 28 into the interior of the photosensitive drum 1. As shown in FIG.

The cylindrical portion 71 has a bearing portion 71c as described above (FIGS. 4 and 11). The bearing portion 71c is rotatably supported by the drum unit bearing member 39R. The inner diameter D2 of the inner peripheral surface 71b of the cylindrical portion 71 is smaller than the inner diameter D9 of the inner peripheral surface 72m of the mounting portion 72, as shown in FIG. Further, as shown in FIGS. 13 and 14, the inner peripheral surface 71b of the cylindrical portion 71 has a tapered shape at the front end (Z1 direction). This tapered shape is an inclined portion (inclined surface) for guiding the main body drive shaft 101 inserted inside the cylindrical portion 71 . When the drum cartridge 13 is inserted into the image forming apparatus main body 100A, the main body drive shaft 101 is aligned with the coupling member 28 so as to reduce the misalignment between the rotation center of the cylindrical portion 71 and the rotation center of the shaft portion 101f. can guide you. Further, as shown in FIG. 8, the inner diameter D2 of the inner peripheral surface 71b is larger than the outer diameter D6 of the shaft portion 101f of the main body drive shaft 101. As shown in FIG. Therefore, after the drum cartridge 13 is completely attached to the image forming apparatus main body 100A, the inner peripheral surface 71b does not come into contact with the rough guide portion 101g.

As shown in FIG. 14, the flange portion 75 has a shape that protrudes outward from the press-fitting portion 72d in the radial direction. When the coupling member 28 is attached to the photoreceptor drum 1, the end face of the photoreceptor drum 1 abuts against the end face 75b of the flange 75, thereby determining the positions of the photoreceptor drum 1 and the coupling member 28 in the Z direction. Shape.

As shown in FIG. 12 , the engaging portion 73 protrudes at least radially inward of the coupling member 28 in order to engage with the main body drive shaft 101 . The engaging portions 73 are arranged at three locations (120° intervals, substantially equal intervals) in the circumferential direction of the coupling member 28 at equal intervals. Similarly, base portions 74 of the support portion are also arranged at three locations at equal intervals in the circumferential direction of the flange member 70 . Further, as shown in FIG. 12, the engaging portion 73 has a drive receiving surface 73a. The base portion 74 also has a backed-up surface 74i and a contact surface 74h.

The drive receiving surface 73a is a driving force receiving portion that receives the driving force from the main body drive shaft 101 by coming into contact with the drive transmission groove 101a. The flange member 70 is a driving force receiving member that receives a driving force via a driving force receiving surface 73a.

A contact surface 74h provided on the base portion 74 of the support portion is a curved surface that contacts the shaft portion 101f when the coupling member 28 is engaged with the main body drive shaft 101. ). The radius R1 of the arc forming the inner diameter of the contact surface 74h is substantially the same as the radius R2 of the shaft portion 101f, as shown in FIG.

The backed-up surface 74i is a surface that abuts on a backup surface 33t of a backup portion 33j of the alignment member 33, which will be described later, and is arranged downstream in the rotational direction with respect to the drive receiving surface 73a (see FIG. 12). Further, as shown in FIG. 15, the backed-up surface 74i and the drive receiving surface 73a are arranged so that the angle J forms an acute angle. That is, the drive receiving surface 73a is inclined with respect to the backup surface 33t of the backup portion 33j.

The drive receiving surface (driving force receiving portion) 73a is movably supported by support portions (73, 74). The supports (73, 74) are U-shaped snap-fits.

A cylinder member 70 forming the coupling member 28 is cylindrical (hollow). That is, the cylinder member 70 is a hollow portion (a portion having a hollow inside) of the coupling member 28 . A base portion 74 of the support portion (73, 74) has a root portion 74a which is a fixed end, and the root portion 74a is fixed to the inner surface of the cylinder 70. As shown in FIG.

At least a part of the support portions (73, 74) is arranged inside the cylinder member 70. As shown in FIG. In this embodiment, the entire support portions (73, 74) are arranged inside the cylinder member 70. As shown in FIG.

As shown in FIGS. 13 and 14 , the base portion 74 extends from the inner surface of the hollow portion (cylinder member 70 ) of the coupling member 28 starting from a base portion (fixed end) 74 a of the base portion 74 . In addition, the base 74 has an elastically deformable portion (elastic deformation portion). Thus, the base portion 74 movably supports the engaging portion 73 provided at its tip (free end).

More specifically, the base portion 74 includes a root side extension portion (fixed end side extension portion) 74t, a folded portion (flexion portion, connecting portion) 74r, and a free end side extension portion (tip side extension portion). 74s. The free end side extending portion 74s is provided with a backed-up surface 74i and a contact surface 74h.

The root-side extending portion 74t extends from the root portion (fixed end) 74a in the Z2 direction (that is, toward the inside of the drum unit 30 in the axial direction) substantially parallel to the rotational axis of the flange member . . That is, the root-side extending portion 74t extends in the Z2 direction toward the folded portion 74r.

The root-side extending portion 74t is arranged radially outward with respect to the engaging portion 73 and the free-end-side extending portion 74s.

The folded portion 74r is formed continuously with the root side extending portion 74t, and is a portion that is also continuously connected with the free end side extending portion 74s. That is, the folded portion 74s is a bent portion provided between the root side extending portion 74t and the free end side extending portion 74s. The folded portion 74s is a connection portion that connects the free end side extension portion 74s and the root side extension portion 74t. In this embodiment, the angle at which the folded portion 74r is bent is made larger than 90°. Specifically, the angle was set to about 180°.

The folded portion 74r and the root side extension portion 74t are elastic portions that can be elastically deformed.

The free-end-side extending portion 74s is an extending portion that extends in the Z1 direction (that is, the outside of the drum unit 30 in the axial direction) substantially parallel to the rotation axis of the flange member 70, starting from the folded portion 74r. The free-end-side extending portion 74s is arranged radially inward with respect to the root-side extending portion 74t.

By bending the integrally formed base portion 74, a free end extension portion 74s and a root side extension portion 74t are formed. With such a configuration, the configuration of the support portions (73, 74) can be simplified.

However, the connecting portion, the root-side extending portion 74t, and the free-end-side extending portion 74s are formed separately (separate members), and the root-side extending portion 74t and the free-end-side extending portion 74s are formed as connecting members (connecting portions). ) is also possible.

The free end side extending portion 74s is also a portion for supporting the drive receiving surface 73a. That is, the free end side extending portion 74s has an engaging portion (protruding portion, projecting portion) 73 on which a drive receiving surface 73a is formed.

The engaging portion 73 is a protrusion provided at the tip of the free end side extending portion 74s and protrudes radially inward. That is, the extending direction (axial direction) of the free end side extending portion 74s and the projecting direction (radial direction) of the engaging portion 73 intersect. The engaging portion 73 is a portion that enters the main body drive transmission groove 101a and engages with the main body drive transmission groove 101a.

The root-side extending portion 74t and the free-end-side extending portion 74s are configured to overlap each other at least partially in the axial direction of the drum unit 30. As shown in FIG. That is, when the root-side extending portion 74t and the free-end-side extending portion 74s are vertically projected onto the axis of the drum unit 30, the projected areas thereof at least partially overlap each other.

A drive receiving surface 73 a provided on the engaging portion 73 is a surface that intersects the rotational direction (circumferential direction) of the coupling member 28 . Further, the drive receiving surface 73a is also a surface extending radially inward from the free end side extending portion 74s.

In this embodiment, the root side extension portion 74t and the free end side extension portion 74s are straight portions extending parallel to the axial direction. However, the configuration is not necessarily limited to such a configuration.

That is, each extending portion (74t, 74s) should extend at least in the axial direction. In other words, the vector extending in the extending direction of each extending portion (74t, 74s) should have a component in the axial direction. As an example, FIGS. 64 and 65 show modifications of this embodiment. As shown in these figures, the root side extending portion 74t may extend in the Z2 direction while being inclined with respect to the axial direction. Further, as shown in FIGS. 64 and 65, the free end side extending portion 74s may also extend in the Z1 direction while being inclined with respect to the axial direction. Even in such a case, the root side extending portion 74t and the free end side extending portion 74s are regarded as extending at least in the axial direction. Also, the root side extension portion 74t and the free end side extension portion 74s are considered to extend in mutually different directions in the axial direction.

Further, as long as the root side extending portion 74t and the free end side extending portion 74s extend at least in the axial direction, they do not have to extend linearly.

The free end of the engaging portion 73 (that is, the tip of the free end side extending portion 74s) is arranged on the Z1 side of the folded portion 74r. A root (fixed end) 74a of the base portion 74 is also arranged on the Z1 side of the folded portion 74r.

The inner surface of the root-side extending portion 74t is arranged so as to have the same diameter as the inner peripheral surface 71b of the cylindrical portion 71 or protrude toward the inner diameter side.

The engaging portion 73 is supported by an elastically deformable base portion 74 , and the engaging portion 73 can move in the radial direction of the coupling member 28 by deformation of the base portion 74 . In other words, the base portion 74 deforms when receiving an external force, and generates a restoring force (elastic force) in the direction of returning to its natural position.

The root-side extending portion 74t deforms so as to incline from the root 74a as a starting point. Further, the folded portion 74r deforms so as to incline the free end side extending portion 74s. As a result, the engaging portion 73 can move in a direction crossing the extending direction of the extending portions (74t, 74s).

Specifically, when the engaging portion 73 contacts the outer peripheral surface of the main body drive shaft 101 , the base portion 74 is elastically deformed so that the engaging portion 73 is directed radially outward along the outer peripheral surface of the main body drive shaft 101 . to move. After that, when the engaging portion 73 comes to the same position (same phase) as the body side drive transmission groove 101a provided on the outer peripheral surface of the body drive shaft 101, the base portion 74 moves toward the direction in which the elastic deformation is eliminated. Then, the engaging portion 73 moves radially inward, and a portion of the engaging portion 73 can enter the main body drive transmission groove 101a.

The drive receiving surface 73a of the flange member 70 has a shape twisted about the axis of the flange member 70, and in this embodiment, the amount of twist is the same as that of the main body drive transmission surface 101b.

The drive receiving surface 73a only needs to have different phases in the rotational direction at the two points in contact with the drive shaft 101 . In other words, the drive receiving surface 73a does not necessarily have a twisted shape as long as it has a function equivalent to that of a twisted surface.

For example, the drive receiving surface 73a may have a shape in which the outer side (Z1 direction side) of the photosensitive drum unit 30 is disposed upstream in the rotation direction of the photosensitive drum 1 with respect to the inner side (Z2 direction side) of the photosensitive drum unit 30 . In other words, a straight line connecting the cylinder inner end and the cylinder outer end along the cylinder axial direction of the engaging portion 73 as the driving force receiving portion is configured to intersect the rotation axis of the cylinder. The drive receiving surface 73a is an inclined portion that is inclined with respect to the axis of the coupling member 28. As shown in FIG.

By forming the drive receiving surface 73a into a twisted shape or an inclined shape in this way, when the drive receiving surface 73a receives a drive, the photoreceptor drum unit 30 has the main body drive shaft 101 on the bearing portion 101d side. A pulling force is added.

As shown in FIG. 14, the engaging portion 73 has an insertion tapered surface 73d on the outside (Z1 direction side) of the photosensitive drum unit 30 in the Z direction as a force receiving portion at the time of attachment. Further, the engaging portion 73 has a withdrawal tapered surface 73e as a force receiving portion at the time of removal inside the photosensitive drum unit 30 in the Z direction (Z2 direction side). This makes it possible to improve the mountability and detachability of the coupling member 28 to and from the main body drive shaft 101 .

At the time of mounting, the insertion tapered surface 73d and the hemispherical shape 101c abut against each other, and the engaging portion 73 is moved radially outward of the drive shaft. Also, during extraction, the withdrawal taper surface 73e and the main body side withdrawal taper 101i abut against each other, and the engaging portion 73 is moved outward in the radial direction of the main body drive shaft 101. As shown in FIG.

Further, as shown in FIG. 14, the engaging portion 73 is arranged to have a length L2 of the drive receiving surface 73 with respect to a distance L1 from the front side end surface of the cylindrical portion 71 to the front side end surface of the engaging portion 73 in the Z direction. are arranged so as to satisfy the relationship of L1>L2.

As shown in FIG. 15, the force receiving portion 77 is arranged downstream of the engaging portion 73 in the rotational direction, and has a receiving surface 77a and ribs 77e. A backup portion 33j of the alignment member 33, which will be described later, is sandwiched between a backed-up surface 74i provided on the free end side extending portion 74s and a receiving surface 77a. The receiving surface 77a and the drive receiving surface 73 are arranged substantially parallel. As shown in FIG. 15, the rib 77e is arranged so as to abut against the inner peripheral surface 72m of the mounting portion 72, starting from the inner diameter side end of the receiving surface 77a and substantially perpendicular to the receiving surface 77a.

At least a part of the support portions (73, 74) and the drive receiving surface 73a is arranged inside the bearing portion 71c in the axial direction of the drum unit 30. As shown in FIG. Therefore, the support portions (73, 74) and the drive receiving surface 73a can be protected by the bearing portion 71c and the bearing member 19R. In particular, in this embodiment, the supporting portions (73, 74) and the drive receiving surface 73a are entirely arranged inside the bearing portion 71c in the axial direction of the drum unit 30. As shown in FIG.

Furthermore, at least a part of the supporting portions (73, 74) is arranged in the internal space of the photosensitive drum 1. As shown in FIG. That is, at least a part of the support portions (73, 74) is located inside the end portion of the photosensitive drum 1 in the axial direction. In other words, when the supporting portions (73, 74) and the photosensitive drum 1 are projected perpendicularly to the axis of the photosensitive drum 1, the projected area of the supporting portions (73, 74) and the photosensitive drum 1 are The projection areas will overlap at least partially in mutual orientation. At least a part of the supporting portions (73, 74) is arranged inside the photosensitive drum 1 also in the radial direction of the drum unit.

Similarly, at least part of the driving force receiving portion (driving receiving surface 73 a ) is arranged inside the photosensitive drum 1 . Therefore, when the driving force receiving surface 73a and the photosensitive drum 1 are projected perpendicularly to the axis of the photosensitive drum 1, the projection area of the driving force receiving surface 73a and the projection area of the photosensitive drum 1 are at least a part of each other. will overlap.

If at least a portion of the support portions (73, 74) and at least a portion of the drive receiving surface 73a are arranged inside the photosensitive drum 1, the support portions (73, 74) and the drive receiving surface 73a are supported by the photosensitive drum 1. can be protected.

In particular, in this embodiment, the support portions (73, 74) as a whole and the drive receiving surface 73a as a whole are arranged inside the photosensitive drum 1. As shown in FIG.

Further, by arranging the base portion 74a, which is the fixed end of the support portions (73, 74), inside the photosensitive drum 1, the following effects are obtained. The fact that the root portion 74a is arranged inside the photoreceptor drum 1 means that the flange member 70 (coupling member 28) is covered with the photoreceptor drum 1 around the root portion 74a and is fixed to the photoreceptor drum 1. be. Since the photoreceptor drum 1 has high rigidity, the portion of the flange member 70 covered with the photoreceptor drum 1 is less likely to deform.

The support portions (73, 74) are elastically deformable starting from the root portion 74a. can be suppressed by the photosensitive drum 1 .

If deformation of the flange member 70 is suppressed, the bearing portion 71c of the flange member 70 can be stably supported by the bearing member 39R. In addition, the supporting portions (73, 74) are supported by the portion of the flange member 70 that is difficult to deform. As a result, the driving force receiving portion (driving receiving surface 73 a ) provided in the supporting portions ( 73 , 74 ) can stably receive the driving force from the main body drive shaft 101 .

Further, by providing the drive receiving surface 73a inside the photosensitive drum 1, the main body drive shaft 101 can be lengthened. The main body drive shaft 101 has its fixed end (bearing portion 101d) supported by the apparatus main body, and its free end (shaft portion 101f) supported by the drum unit. In this case, the longer the distance between the bearing portion 101d and the shaft portion 101f, the less likely the main body drive shaft 101 will be greatly inclined with respect to the drum unit. That is, when the cartridge 7 is attached to the apparatus main body, the main body drive shaft 101 and the drum unit can be easily kept parallel.

Therefore, by arranging the drive receiving surface 73a inside the photosensitive drum 1, the shaft portion 101f can be inserted into the photosensitive drum 1 and the shaft portion 101f can be supported inside the photosensitive drum 1. . With such a configuration, it is easy to secure the length of the main body driving shaft 101 (the distance between the bearing receiving portion 101d and the shaft portion 101f) while suppressing an increase in the size of the apparatus main body.

(Description on manufacturing method)
The flange member 70 of this embodiment is manufactured by injection molding (insert molding) using a mold.

The configuration of the mold used when molding the flange member 70 will be described with reference to FIG. 17 .

The flange member 70 has a shape in which a flange portion 75 protrudes most outward in the radial direction. When molding such a shape, a mold as shown in FIG. 17 is preferable.

Specifically, as shown in the drawing, the mold has a two-body structure of a left mold (cylindrical mold 60) and a right mold (mounting part side mold 61). By matching the left and right molds, a space (mold cavity) having the same shape as the molded product is formed. The flange member 70 is formed by pouring the material into this space and solidifying it in the mold. The mold has a mold parting 62 (a surface for dividing the mold, a surface for fitting the molds), which is a portion where the left and right molds are joined, near the space forming the flange portion 75 . The cylindrical mold 60 has a shape with a space for molding the outer circumference of the cylindrical portion 71 . Similarly, the mounting portion side mold 61 has a shape having a space for molding the mounting portion 72 .

When forming the flange member 70 using such a mold, it is preferable to use a thermoplastic resin from the viewpoint of mass productivity. Specifically, materials such as POM and PPS are considered suitable. However, other materials may be selected as appropriate to meet requirements such as strength. Specifically, it is conceivable to use a thermosetting resin, a metal material, or the like.

As described above, the engaging portion 73 has an insertion taper 73d at one end and an extraction taper 73e at the other end in the Z direction. Therefore, it is difficult to arrange the die part 62 of the mold on either end face of the engaging portion 73 in the Z direction. This is because when a mold that is divided into two parts is used, it is difficult to remove the molded flange member 70 from the mold if the mold split 62 is arranged on either of the two end surfaces of the engaging portion 73. It is for the sake of becoming. In other words, when the two molds are to be removed from the engaging portion 73 after the engaging portion 73 is formed, at least one of the molds is caught by the engaging portion 73 and cannot be moved.

It is easier to manufacture the mold if the mold split 62 is made as straight as possible. As a result, it becomes possible to manufacture the mold split 62 with high precision. Therefore, by making the mold split 62 as straight as possible, the possibility of resin leakage or the like occurring can be reduced.

In order to straighten the mold part 62 of the engaging portion 73, it is necessary to arrange the drive receiving surface 73a at least toward the inner side (Z2 side) of the photosensitive drum unit 30 from the insertion taper 73d. Therefore, in this embodiment, the end of the insertion taper 73d and the end of the drive receiving surface 73a are arranged at the same position in the Z direction.

Further, when molding the flange member 70 of this embodiment, the mold splits 62 are arranged as follows. That is, the drive receiving surface 73 a and the surface of the base 74 that can be seen from the Z2 direction side are formed by the mounting portion side mold 61 . In addition, the insertion taper 73d and the surface of the base portion 74 that can be seen from the Z1 direction side are formed by the cylindrical mold 60. As shown in FIG. As described above, the inner surface of the root-side extending portion 74t is arranged to have the same diameter as the inner peripheral surface 71R of the cylindrical portion 71 or protrude toward the inner diameter side. As a result, it is possible to prevent the root-side extending portion 74t from being caught by the cylindrical portion-side mold 60 and hindering the movement of the cylindrical portion-side mold 60 .

When the flange member 70 is viewed from the Z direction (when the flange member 70 is viewed along the axial direction), as shown in FIG. It should be placed so that it does not wrap. That is, when the flange member 70 is viewed along the axial direction, the force receiving portion 77 needs to be arranged with a gap from the engaging portion 73 and the base portion 74 . Considering the thickness of the mold, the force receiving portion 77 is desirably arranged with a gap of about 1 mm from the engaging portion 73 and the base portion 74 .

(Description of the alignment member)
Next, the configuration of the alignment member (positioning member) 33 will be described with reference to FIGS.

In this embodiment, the alignment member 33 has a concave portion (inverted conical shape 33a) tapered toward the bottom. The inverted conical shape 33 a is a substantially conical depression (recess), which is arranged on the axis of the drum unit 30 . Further, in the axial direction of the drum unit 30, it is arranged inside the drive receiving surface 73a. The detailed shape of the alignment member 33 will be described below.

As shown in FIG. 18, the alignment member 33 has an inverted conical shape 33a, a fitting portion 33b, a retaining portion 33c, and a backup portion 33j.

As shown in FIG. 19, the coupling member 28 is constructed by assembling the alignment member 33 from the Z2 side to the Z1 side of the flange member 70 along the rotation axis.

As shown in FIG. 10, the inverted conical shape 33a is arranged inside the photosensitive drum unit 30 (Z2 direction side) from the engaging portion 73. As shown in FIG. Further, the flange member 70 and the alignment member 33 are assembled so that the center of the inverted conical shape 33a and the center of the photosensitive drum 1 are aligned when the alignment member 33 is viewed along the Z direction.

The inverted conical shape 33a has a contact portion 33e that contacts a hemispherical shape 101c that is a hemispherical shape at the tip of the main body drive shaft 101 when the photosensitive drum 1 is rotationally driven. In addition, the inverted conical shape 33a is a substantially inverted conical shape (a shape recessed in a substantially conical shape). As shown in FIG. 10, the center 101h of the hemispherical shape 101c of the main body drive shaft 101 is in contact with the contact portion 33e in the Z direction. It is attached to the flange member 70 so that it is within range.

The drum unit 30 is positioned with respect to the main body drive shaft 101 by the contact portion 33e provided on the inverted conical shape 33a coming into contact with the hemispherical shape 101c of the main body drive shaft 101. As shown in FIG.

In other words, the inverted conical shape 33 a can determine the axial position and the radial position of the drum unit 30 with respect to the main body drive shaft 101 . That is, the inverted conical shape 33a serves as a radial positioning portion as well as an axial positioning portion.

Note that the radial positioning portion and the longitudinal positioning portion need not be conical recesses such as the inverted conical shape 33a. The radial positioning portion and the longitudinal positioning portion may have any shape as long as they can position the photosensitive drum unit 30 with respect to the main body drive shaft 101 when they come into contact with the main body drive shaft 101 . For example, they are preferably recesses (recesses) that taper towards the bottom. As such, a non-conical pyramidal shape such as a pyramid (such as a square pyramid) can also be used. However, if, like the inverted conical shape 33a of this embodiment, the conical concave portion is symmetrical with respect to the axis of the coupling member 28, the position of the coupling member 28 (the position of the drum unit 30) can be determined with particularly high accuracy. can have

Since the inverted conical shape 33a only needs to have a region for contact with the main body drive shaft 101, the non-contact region may have any shape. For example, the bottom of the inverted conical shape 33a, which is the portion that does not come into contact with the main body drive shaft 101, may be omitted, and the inverted conical shape 33a may be a hollow recess.

The fitting portion 33b is provided for attaching the alignment member 33 to the flange member 70, and as shown in FIG. have. Further, the fitting portion 33b is arranged inside the photosensitive drum unit 30 (Z2 direction side) from the contact portion 33e.

As shown in FIG. 18 , the retaining portion 33 c has a hook shape and is shaped to prevent the alignment member 33 from falling off from the flange member 70 . Further, as shown in FIG. 11, the flange member 70 has a hole shape 72b at a location corresponding to the retaining portion 33c.

As shown in FIG. 15, the backup portion 33j is assembled in the gap between the backed-up surface 74i of the flange member 70 and the receiving surface 77a, and has a shape that prevents the engaging portion 73 from tilting toward the upstream side in the rotational direction. . Therefore, the thickness of the backup portion 33j is set substantially equal to the gap between the backed-up surface 74i and the receiving surface 77a.

That is, the backup portion 33j is a portion that prevents the engagement portion 73 (drive receiving surface 73a) from moving in the circumferential direction of the flange member 70 by coming into contact with the backed-up surface 74i. The alignment member 33 is a backup member having a backup portion 33j.

The alignment member 33 is also a positioning member for determining the relative position of the flange member 70 (drum unit 30 ) with respect to the main body drive shaft 101 . A concave portion (inverted conical shape 33a) provided in the alignment member 33 contacts the tip of the main body drive shaft 101 as a positioning portion. As a result, both the relative position of the flange member 70 in the axial direction and the relative position of the flange member 70 in the radial direction with respect to the main body drive shaft 101 are determined.

A circle passing through the ridgeline of the backup portion 33j on the side of the engaging portion 73 when viewed from the Z direction is arranged so that its center is the same as the inverted conical shape 33a, and the diameter of the circle is D8. The diameter D8 is approximately the same as the outer diameter D5 of the shaft portion 101f of the main body drive shaft 101, or is created so that D8≧D5 when the respective dimensional accuracies are considered. In addition, as shown in FIG. 16, the backup portion 33j is arranged so as to overlap the drive receiving surface 73a in the Z direction.

[Attachment of Cartridge to Image Forming Apparatus]
Attachment/detachment of the drum cartridge 13 to/from the main body of the image forming apparatus will be described with reference to FIGS. 20 and 21. FIG.

FIG. 20 is a perspective view for explaining the attachment of the drum cartridge 13 to the image forming apparatus main body 100A.

FIG. 21 is a sectional view for explaining the mounting operation of the drum cartridge 13 to the image forming apparatus main body 100A.

The image forming apparatus main body 100A of this embodiment employs a configuration in which the cartridge can be mounted in a substantially horizontal direction. Specifically, the image forming apparatus main body 100A has a space in which the cartridge can be mounted. A cartridge door 104 (front door) for inserting the cartridge into the above-described space is provided on the front side of the image forming apparatus main body 100A (the direction in which the user stands during use).

As shown in FIG. 20, the cartridge door 104 of the image forming apparatus main body 100A is openable and closable. When the cartridge door 104 is opened, a cartridge lower guide rail 105 for guiding the drum cartridge 13 is arranged on the bottom surface of the above-mentioned space, and a cartridge upper guide rail 106 is arranged on the upper surface. The drum cartridge 13 is guided to the mounting position by upper and lower guide rails (105, 106) provided above and below the aforementioned space. The drum cartridge 13 is inserted into the mounting position substantially along the axis of the photosensitive drum unit 30 .

The operation of attaching and detaching the cartridge to and from the image forming apparatus main body 100A will be described below with reference to FIG.

As shown in FIG. 21A, the drum unit bearing member 39R and the photosensitive drum 1 do not contact the intermediate transfer belt 5 when the drum cartridge 13 starts to be inserted. In other words, the dimension relationship is such that the photosensitive drum 1 and the intermediate transfer belt 5 do not come into contact with each other when the rear end of the drum cartridge 13 in the insertion direction is supported by the cartridge lower guide rail 105 .

Next, as shown in FIG. 21B, the image forming apparatus main body 100A is provided with a rear side cartridge lower guide 107 protruding upward in the gravity direction from the cartridge lower guide rail 105 on the rear side of the cartridge lower guide rail 105 in the insertion direction. . The rear side cartridge lower guide 107 has a tapered surface 107a on the front side in the insertion direction of the drum cartridge 13 . As it is inserted, the drum cartridge 13 rides on the tapered surface 107a and is guided to the mounting position.

The position and shape of the inner cartridge lower guide 107 may be set so that a part of the cartridge does not rub against the image forming area 5A of the intermediate transfer belt 5 when the cartridge is inserted into the apparatus main body 100A. Here, the image forming area 5A indicates an area where a toner image to be transferred onto the recording material 12 of the intermediate transfer belt 5 is carried. Further, in this embodiment, among the cartridges maintaining the mounting posture, the unit bearing member 39R provided on the far side in the insertion direction of the drum cartridge 13 protrudes most upward in the direction of gravity. Therefore, the arrangement and shape of each element may be appropriately selected so that the trajectory (hereinafter referred to as an insertion trajectory) drawn by the end of the drum unit bearing member 39R on the farthest side in the insertion direction during insertion does not interfere with the image forming area 5A. good.

After that, as shown in FIG. 21(c), the drum cartridge 13 is further inserted into the image forming apparatus main body 100A from the state where it has run over the inner cartridge lower guide 107. As shown in FIG. Then, the drum unit bearing member 39R abuts against the inner cartridge positioning portion 108 provided in the image forming apparatus main body 100A. At this time, the drum cartridge 13 (photosensitive drum unit 30) is tilted by about 0.5 to 2 degrees from the state in which it is completely attached to the image forming apparatus main body 100A (FIG. 21(d)). That is, in the insertion direction of the drum cartridge 13, the downstream side of the drum cartridge 13 (photosensitive drum unit 30) is raised more than the upstream side.

FIG. 21(d) is a diagram showing the state of the apparatus body and the cartridge when the cartridge door 104 is closed. The image forming apparatus 100A has a front side cartridge lower guide 109 on the front side of the cartridge lower guide rail 105 in the insertion direction. The front side cartridge lower guide 109 is configured to move up and down in conjunction with the opening and closing of the cartridge door (front door) 104 .

When the cartridge door 104 is closed by the user, the front side cartridge lower guide 109 is raised. Then, the drum unit bearing member 39L and the front side cartridge positioning portion 110 of the image forming apparatus main body 100A come into contact with each other, and the drum cartridge 13 is positioned with respect to the image forming apparatus main body 100A.

By the above operation, the mounting of the drum cartridge 13 to the image forming apparatus main body 100A is completed.

Further, the removal of the drum cartridge 13 from the image forming apparatus main body 100A is performed in the reverse order of the insertion operation described above.

Since the oblique mounting structure is adopted as described above, it is possible to suppress rubbing between the photosensitive drum and the intermediate transfer belt when mounting the drum cartridge 13 to the apparatus main assembly 100A. Therefore, it is possible to suppress the occurrence of minute scratches (scratches) on the surface of the photosensitive drum or the surface of the intermediate transfer belt.

Further, the configuration disclosed in this embodiment can simplify the configuration of the image forming apparatus main body 100A compared to the configuration in which the entire cartridge is lifted up after the cartridge is horizontally moved and mounted in the apparatus main body. .

[Process of Engaging Coupling Member with Main Body Drive Shaft]
Next, the engagement process between the coupling member 28 and the main body drive shaft 101 will be described in detail with reference to FIGS.

FIG. 22 is a cross-sectional view for explaining the mounting operation of the coupling member 28 to the main body drive shaft 101. As shown in FIG.

FIG. 23 shows coupling to the main body drive shaft 101 when the main body drive shaft 101 rotates from a state in which the main body drive transmission groove 101a and the engaging portion 73 (the drive receiving surface 73a) are out of phase and the phases match. FIG. 10 is a cross-sectional view for explaining the mounting operation of the member 28;

FIG. 22(a) is a diagram showing a state in which the coupling member 28 has started to engage with the main body drive shaft 101. FIG. FIG. 22E shows a state in which the drum cartridge 13 is attached to the image forming apparatus main body 100A. In particular, FIG. 23(e) shows a state in which the front side cartridge lower guide 109 is raised as the cartridge door 104 is closed, and the drum cartridge 13 is positioned with respect to the image forming apparatus main body 100A.

Here, FIGS. 22(b) to 22(d) are diagrams for explaining the mounting process of the coupling member 28 and the main body drive shaft 101 between FIGS. 22(a) and 22(e). Note that the main body drive shaft 101 hangs downward in the direction of gravity by a minute angle due to its own weight.

FIG. 23(a) is a diagram for explaining a state in which the main body drive transmission groove 101a and the engaging portion 73 (drive receiving surface 73a) are out of phase.

As described with reference to FIG. 21B, the drum cartridge 13 rides on the inner cartridge lower guide 107 . 21(a) to 21(b), the drum cartridge 13 is tilted by about 0.5 to 2 degrees while gradually increasing the tilt. Then, the drum cartridge 13 rides on the inner cartridge lower guide 107. Similarly, as shown in FIG. It is inserted into the main body drive shaft 101 in a state inclined by about 0.5 to 2° with respect to the time (shown in FIG. 22(e)).

As shown in FIG. 6, the body drive shaft 101 is cantilevered on the bearing portion 101d. Further, the gear portion 101e meshes with a gear (not shown) that transmits drive to the gear portion 101e. FIG. 22( a ) is a diagram showing a state in which the main body drive shaft 101 is not in contact with the coupling member 28 . In this state, the drum cartridge 13 is tilted by θ1 in a direction determined by its own weight and the engagement direction with respect to the state in which the drum cartridge 13 is positioned with respect to the image forming apparatus main body 100A (shown in FIG. 22(e)). .

As shown in FIG. 22(b), the tip of the inner peripheral surface 71b of the cylindrical portion 71 of the coupling member 28 first contacts the rough guide portion 101g of the main body drive shaft 101. As shown in FIG. As shown in the figure, the main body drive shaft 101 is configured to be cantilevered on the bearing receiving portion 101d. Therefore, the rough guide portion 101g of the main body drive shaft 101 is inserted into the main body drive shaft 101 so as to follow the inner peripheral surface 71b of the coupling member . As described above, the engaging portion 73 has a distance L1 from the front side end surface of the cylindrical portion 71 to the front side end surface of the engaging portion 73 in the Z direction, and the length L2 of the drive receiving surface 73 is L1> They are arranged so as to have the relationship of L2 (shown in FIG. 14). Therefore, the rough guide portion 101g of the main body drive shaft 101 runs along the inner peripheral surface 71b of the coupling member 28 before the hemispherical shape 101c at the tip of the main body drive shaft 101 hits the engaging portion 73. As shown in FIG. As a result, the main body drive shaft 101 is guided with respect to the coupling member 28 . As a result, the hemispherical shape 101c at the tip of the main body drive shaft 101 can be prevented from hitting an unexpected place on the engaging portion 73 or the base portion 74 and damaging them.

As shown in FIG. 22C, when the coupling member 28 is further inserted from FIG. The hemispherical shape 101c of the tip abuts. The body drive shaft 101 is guided substantially in the center of the three engaging portions 73 by the slope of the insertion tapered surface 73d and the spherical shape of the hemispherical shape 101c.

Further, when the coupling member 28 is inserted into the main body drive shaft 101, the base portion 74 is elastically deformed radially outward so that the engaging portion 73 follows the hemispherical shape 101c. As a result, as shown in FIG. 23( a ), the engaging portion 73 moves (retreats) to the outer diameter of the shaft portion 101 f of the main body drive shaft 101 . As a result of this movement, as shown in FIG. 22(d), the coupling member 28 is disengaged until the withdrawal taper surface 73e of the engaging portion 73 is located farther in the Z direction than the main body side withdrawal taper 101i of the main body drive shaft 101. It is attached to the main body drive shaft 101 . As described above, the base portion 74 has the elastically deformable root side extension portion 74t and the folded portion 74r. When the engaging portion 73 moves radially outward, the root-side extending portion 74t and the folded-back portion 74r of the base portion 74 are each elastically deformed. Therefore, it is possible to deform radially outward with a small force. Therefore, the mounting force of the drum cartridge 13 to the image forming apparatus main body 100A can be kept low.

Moreover, the base portion 74 can be arranged in a limited space in the Z direction by having the folded portion 74r.

As described above, the mounting force of the drum cartridge 13 to the image forming apparatus main body 100A can be kept low without increasing the size of the flange member 70 in the Z2 direction.

After that, as described above, the drum cartridge 13 is lifted so that the drum unit bearing member 39L of the drum cartridge 13 abuts against the front side cartridge positioning portion 110 . By lifting the drum cartridge 13, the drum cartridge 13 is positioned with respect to the image forming apparatus main body 100A (shown in FIG. 21(d)). This operation of the drum cartridge 13 eliminates the inclination of the coupling member 28 as shown in FIG. 22(e).

Then, when the main body drive shaft 101 rotates, as shown in FIG. 23(b), the main body drive transmission groove 101a and the engaging portion 73 are in the same phase. As a result, the elastic deformation of the base portion 74 is at least partially eliminated, a portion of the engaging portion 73 enters the main body drive transmission groove 101a, and the coupling member 28 and the main body drive shaft 101 are engaged.

When the main body drive transmission groove 101a and the engaging portion 73 are in phase with each other, the elastic deformation of the base portion 74 is released at the stage of FIG. The driving force of 101 can be transmitted to the drum cartridge 13 through the coupling member 28 .

As described above, when the drum cartridge 13 is attached to the apparatus main body 100A, the main body drive transmission groove 101a and the engaging portion 73 are brought into an engaging state. Therefore, it is not necessary to move the main body drive shaft 101 to engage with the coupling member 28 . In other words, it is not necessary to provide the apparatus main body 100A of the image forming apparatus with a mechanism for moving the main body drive shaft 101 so as to engage with the coupling member 28 . A mechanism for engaging the main body drive shaft 101 with the coupling member 28 after the drum cartridge 13 is attached to the image forming apparatus main body 100A can be omitted from the apparatus main body 100A.

When the drum cartridge 13 is attached to the apparatus main body 100A, the engaging portion 73 of the coupling member 28 is retracted radially outward by coming into contact with the main body drive shaft 101. FIG. The engaging portion 73 is configured to engage with the groove of the main body drive shaft 101 (the main body drive transmission groove 101a) by moving radially inward.

Here, it is also possible to provide a groove for receiving drive in the coupling member, and provide a movable portion that can be engaged with the groove by moving in the radial direction on the main body drive shaft 101 side. However, compared to the drum cartridge 13, the image forming apparatus main body 100A is required to have higher durability. It is preferable to provide the movable portion (engagement portion 73) that moves in the radial direction on the side of the coupling member 28 of the drum cartridge 13 as in this embodiment, in order to increase the durability of the image forming apparatus main body 100A.

[Driving Coupling Member by Main Body Drive Shaft]
Transmission of rotational drive from main body drive shaft 101 to coupling member 28 will be described with reference to FIG.

When the drive receiving surface 73a of the coupling member 28 abuts against the main body drive transmission surface 101b, the cleaning blade 26, charging roller 22, etc. apply a load to the photosensitive drum unit 30. FIG. That is, the drive receiving surface 73a rotates integrally with the drive transmission surface 101b while receiving the load (driving force) F1.

When the driving force F1 is received by the drive receiving surface 73a, the angle J formed by the surface to be backed up 74i and the surface to be backed up 73a is an acute angle. direction component Fh. As shown in FIG. 15, the vertical component Fv is transmitted to the backed-up surface 74i of the engaging portion 73 opposite to the drive receiving surface 73a. Since the engaging portion 73 is backed up by the mounting portion 72 via the backup portion 33j and the rib 77e, the engaging portion 73 is hardly deformed downstream in the rotational direction.

When the engaging portion 73 receives the parallel direction component Fv, the contact surface 74h contacts the shaft portion 101f of the main body drive shaft 101, and the engaging portion 73 is backed up.

Further, the force component Fv parallel to the backed-up surface 74i urges the engaging portion 73 (drive receiving surface 73a) radially inward toward the inside of the drive transmission groove 101a.

That is, the backup surface 33t of the backup portion 33j and the backed-up surface 74i are inclined with respect to the drive receiving surface 73a. As a result, when the drive receiving surface 73a receives force from the drive transmission groove 101a of the main body drive shaft 101 and the surface to be backed up 74i contacts the backup surface 33t, the engaging portion 73 moves radially inward along the backup surface 33t. move to That is, the backup surface 33t and the backed-up surface 74i are inclined with respect to the drive receiving surface 73a. A force is generated to urge it toward.

In the cross section shown in FIG. 15, the straight line extending along the drive receiving surface 73a and the straight line extending along the backup surface 33t intersect outside the driving force receiving surface 73a in the radial direction of the coupling member. ing.

In addition, in the radial direction of the coupling member 28, the backup surface 33t is inclined such that the inner diameter side thereof is located downstream of the outer diameter side thereof in the rotational direction. The same applies to the surface to be backed up 74i.

A driving force receiving surface 73 a provided on the engaging portion 73 is an inclined portion that is inclined with respect to the moving direction of the engaging portion 73 . The engaging portion 73 is movable so as to retreat outward in the radial direction of the coupling member 28, but the driving force receiving surface 73a is inclined with respect to that direction.

In other words, the driving force receiving surface 73a is inclined so that the driving force receiving surface 73a bites into the driving force transmitting groove 101a while the driving force receiving surface 73a is in contact with the driving force transmitting groove 101a. Therefore, when the drive receiving surface 73a receives the driving force from the drive transmission groove 101a, the engaging portion 73 is difficult to retreat from the drive transmission groove 101a. That is, the engagement state between the engagement portion 73 and the drive transmission groove 101a is stabilized.

More specifically, the drive receiving surface 73a is arranged upstream in the rotational direction of the coupling member 28 on the inner diameter side (front end side) of the coupling member 28 than on the outer diameter side (rear end side). That is, the drive receiving surface 73a is inclined so as to face at least the radially outer side of the coupling member 28 . That is, the normal vector extending perpendicularly to the drive receiving surface 73a toward the side facing the drive receiving surface 73a has an outward component in the radial direction.

Therefore, when the coupling member 28 (photosensitive drum unit 30) rotates, the force received by the drive receiving surface 73a works in the direction of engaging the engaging portion 73 with the main body drive transmission groove 101a. That is, the engaging portion 73 is urged radially inward by the driving force received by the drive receiving surface 73a. As a result, the engagement state between the engaging portion 73 and the main body drive transmission groove 101a is stabilized, and disengagement between the engaging portion 73 and the main body drive transmission groove 101a is suppressed.

As a result of the above configuration, the drive receiving surface 73a can be stably brought into contact with the main body drive receiving surface 101a, and the photosensitive drum unit 30 can be drawn into the main body drive shaft 101 toward the bearing portion 101d. Further, even if the load F1 fluctuates, since the engaging portion 73 is backed up as described above, deformation of the engaging portion is suppressed. Therefore, the amount of rotation of the photosensitive drum 1 does not substantially change, and as a result, the image quality can be maintained.

In this embodiment, the backup portion 33i is provided on the alignment member (positioning member) 33. As shown in FIG. However, the backup portion 33 i may be provided on a member different from the alignment member 33 .

That is, the backup portion 33i may be provided on a member different from the positioning portion (inverted conical shape 33a) for positioning the drum unit 30 with respect to the main body drive shaft 101. FIG.

[Removal of Coupling Member from Main Body Drive Shaft]
An operation of removing the coupling member 28 from the main body drive shaft 101 will be described with reference to FIG.

FIG. 24 is a cross-sectional view for explaining the operation of removing the coupling member 28 from the main body drive shaft 101. As shown in FIG.

As shown in FIG. 24(a), when the main body drive shaft 101 stops rotating, the drive receiving surface 73a and the main body drive transmission surface 101b are in contact with each other. In this state, part of the engaging portion 73 enters the main body drive transmission groove 101a.

When the cartridge door 104 is opened, the front cartridge lower guide 109 is lowered, and the drum unit bearing member 39L is separated from the front cartridge positioning portion 110 of the image forming apparatus main body 100A. At this time, the coupling member 28 and the main body drive shaft 101 are tilted by about 0.5 to 2° with respect to the mounting completion state (Z direction), as shown in FIG. 24(b).

When the removal of the drum cartridge 13 from the image forming apparatus main body 100A is started, as shown in FIG. When the withdrawal taper surface 73e abuts against the main body side withdrawal taper 101i, the base portion 74 begins to elastically deform, causing the engaging portion 73 to move radially outward along the main body side withdrawal taper 101i.

Further, when the coupling member 28 is removed from the main body drive shaft 101 , the base portion 74 is further elastically deformed to move the engaging portion 73 to the outer diameter of the shaft portion 101 f of the main body drive shaft 101 . By moving the engaging portion 73 to the outer diameter of the shaft portion 101f, the coupling member 28 can be removed from the main body drive shaft 101 as shown in FIG. 24(d).

Further, when the coupling member 28 is removed from the main body drive shaft 101, as shown in FIG. 24(e), the elastic deformation of the base portion 74 is released, and the position of the engaging portion 73 also returns to the position before the elastic deformation. .

As described above, by using the coupling member of this embodiment, it is possible to suppress an increase in the size of the flange member 70 in the Z2 direction. Further, the mounting force of the drum cartridge 13 to the image forming apparatus main body 100A can be kept low, the change in the amount of rotation of the photosensitive drum 1 can be suppressed, and the image quality can be maintained.

In the present embodiment, the base portion 74 is provided with one folded portion 74r. However, a configuration having a plurality of folded portions 74r is also possible as long as it can be arranged in the space of the inner peripheral surface 72m of the coupling member 28. be.

For example, a configuration in which the following configurations are arranged in order from the fixed end of the base portion 74 toward the free end is also conceivable. That is, (1) an extension portion extending inward in the axial direction, (2) a folded portion, (3) an extension portion extending outward in the axial direction, (4) a folded portion, and (5) in the axial direction Inwardly extending extensions. In this case, the base 74 has three extensions and is S-shaped. Regardless of whether there is one folded portion or multiple folded portions, the base portion 74 has at least a first extension portion and a second extension portion extending in mutually different directions in the axial direction. In the present embodiment shown in FIGS. 13, 14, etc., one of the root side extension portion 74t and the free end side extension portion 74s extending in directions different from each other corresponds to the first extension portion, The other corresponds to the second extension.

For example, if the free end side extending portion 74s arranged on the most free end side of the supporting portion is the first extending portion, the root side extending portion 74t connected thereto is the second extending portion. In this case the first extension (74s) extends from the second extension (74t) towards the free end of the support and the second extension (74t) extends from the fixed end of the support. It can also be said that it extends toward the first extension portion (74s).

<Example 2>
A second embodiment will be described with reference to FIGS. 25 to 30. FIG.

FIG. 25 is a cross-sectional view of the coupling member 128 according to this embodiment cut along the rotation axis center (rotation axis center). FIG. is a cross-sectional view cut at a position passing through the drive receiving surface 73a in a direction perpendicular to .

27 is a view of the flange member 170 according to this embodiment viewed from the outside in the Z direction, and a cross-sectional view. FIG. 28 is a view of the inner cylindrical member 140 according to this embodiment viewed from the Z1 side to the Z2 side. 29 is an explanatory cross-sectional view showing the procedure for assembling the coupling member 128 according to this embodiment. FIG. It is a view seen from the side. When the elements of this embodiment correspond to the elements described in Embodiment 1, they are given the same names. Regarding those elements, the configurations and actions that are different from the elements of the above-described embodiment will be described in detail, and the description of the same points as the above-described elements may be omitted.

Elements that are substantially the same as those of the above-described embodiments are given the same names and the same reference numerals, and detailed descriptions thereof are omitted.

In Example 1, the coupling member 28 is configured by being divided into two parts, the flange member 70 and the alignment member 33 . In contrast, in this embodiment, the coupling member 128 is composed of a flange member 170 and an inner cylindrical member 140, as shown in FIG.

More specifically, the flange member 170 has a mounting portion 172, a cylindrical portion 171, a collar portion 175, a force receiving portion 177, an alignment portion 133a, and a cylindrical member pressing portion 178, as shown in FIG. As shown in FIG. 28, the inner cylindrical member 140 has a base portion 174, an engaging portion 173, a fitting portion 140a, a retaining portion 140b, and a rotation preventing portion 140c.

The base portion 174 and the engaging portion 173 form a support portion for supporting the driving force receiving portion (drive receiving surface 173a), like the base portion 74 and the engaging portion 73 of the first embodiment. This support (174, 173) is a snap fit with a U shape. The inner cylindrical member 140 is a driving force receiving member that receives driving force from the apparatus main body through a driving force receiving surface 173 a (see FIG. 28) provided on the engaging portion 173 .

The flange member 170 is a transmitted member to which driving force is transmitted from the inner cylindrical member 140 .

(Description on flange member)
As described above, the flange member 170 has a mounting portion 172, a cylindrical portion 171, a collar portion 175, a force receiving portion 177, an inverted conical shape 133a, and a cylindrical member pressing portion 178, as shown in FIG.

The attachment portion 172 is a portion for attachment to the photosensitive drum 1, like the attachment portion 72 of the first embodiment. The mounting portion 172 is adhered to the inner circumference of the photoreceptor drum 1 or press-fitted to the inner circumference of the photoreceptor drum 1 .

The cylindrical portion 171 has a bearing portion equivalent to the bearing portion 71c of the first embodiment, and is rotatably supported by the drum unit bearing member 39R by this bearing portion. Similarly, it is a shape for determining the positions of the photosensitive drum 1 and the coupling member 128 in the Z direction.

When the coupling member 128 is driven by the main body drive shaft 101, the force receiving portion 177 abuts on a backed-up surface 174i of the inner cylinder, which will be described later, to prevent the engaging portion 173 from deforming downstream in the rotational direction. It is a shape to prevent. Therefore, the coupling member 128 is arranged on the downstream side of the engaging portion 173 in the rotational direction.

The force receiving portion 177 has a receiving surface 177a parallel to the backed-up surface 174i and in contact with the backed-up surface 174i, and a rib 177e arranged perpendicular to the receiving surface 177a and extending from the inner diameter end of the receiving surface to the mounting portion 172. have

The receiving surface 177 a is a backup portion that prevents the engaging portion 173 (drive receiving surface 173 a ) from moving in the circumferential direction of the coupling member 128 . Further, the flange member 170 is a backup member having a backup portion (receiving surface 177a).

Further, the driving force is transmitted from the inner cylindrical member 140 to the receiving surface 177a by contacting the backed-up surface 174i. That is, the driving force received by the drive receiving surface 173a of the engaging portion 173 from the apparatus body is transmitted from the inner cylindrical member 140 to the cylinder member 170 via the backed-up surface 174i and the receiving surface 177a. The receiving surface 177 a also serves as a transmitted portion for transmitting driving force from the inner cylindrical member 140 .

The inverted conical shape 133a is a substantially inverted conical shape as in the first embodiment. The flange member 170 is arranged so that the center 101h of the hemispherical shape 101c of the main body drive shaft 101 is within the range of the drive receiving surface 173a in the state of contact with the contact portion 133e in the Z direction. be.

The cylindrical member holding portion 178 is a gap provided on the far side (Z2 side) of the force receiving portion 177 .

As shown in FIG. 25, the radius R19 of the portion of the inner peripheral surface 172m of the mounting portion 172 corresponding to the engaging portion 173 in the radial direction is larger than the radius R12 of the inner peripheral surface 171b of the cylindrical portion 171. As shown in FIG.

(Description on the inner cylinder)
As described above, the inner cylinder 140 has the base portion 174 of the support portion, the engagement portion 173 of the support portion, the fitting portion 140a, the retaining portion 140b, and the rotation preventing portion 140c (FIG. 28).

The engaging portion 173 has a drive receiving surface 173a as in the first embodiment.

As in the first embodiment, the base portion 174 has a root side extension portion 174t, a folded portion 174r, and a free end side extension portion 174s. The free end side extending portion 174s has a backed-up surface 174i and a contact surface 174h.

In the present embodiment, each of the root-side extension portion 174t and the free-end-side extension portion 174s has an extending direction different from that of each of the root-side extension portion 74t and the free-end-side extension portion 74s of the first embodiment. It's the opposite.

The root-side extending portion 174t extends from the root-side extending portion 174a substantially parallel to the rotation axis of the flange member 170 in the Z1 direction (outside in the axial direction of the drum unit). It is arranged radially outward with respect to.

The folded portion 174r is a bent portion that continuously connects the fixed end side of the root side extension portion 174s and the free end side of the root side extension portion 174t.

An engaging portion 173 is provided over substantially the entire area of the root side extending portion 174s. The engaging portion 173 is a protrusion included in the root side extending portion 174s, and the engaging portion 173 is provided with a driving force receiving portion (a driving force receiving surface 173a).

The base portion 174 is elastically deformed at each of the root side extending portion 174t and the folded portion 174r. Compared to a configuration in which only the root-side extending portion 174t is elastically deformed, it can be deformed radially outward with a smaller force. This is the same as the first embodiment.

The free end side of the engaging portion 173 (the tip side of the free end extending portion 174s) and the root 174a of the base portion 174 are both arranged on the Z2 side of the folded portion 174r.

The fitting portion 140a is arranged on the inner side of the base portion 174 and the engaging portion 173, and is fitted to the outer peripheral surface of the alignment portion 133a, so that the flange member 170 and the inner cylindrical member 140 are aligned with high accuracy. is part of

The retaining portion 140 b is a portion for preventing the inner cylindrical member 140 from falling off the flange member 170 . More specifically, after the inner cylindrical member 140 is incorporated into the flange member 170, it enters the cylindrical member pressing portion 178 to prevent it from coming off. As shown in FIG. 29(a), the retainer portion 140b is located on the upstream side in the rotational direction of the flange member 170 when it is incorporated in the inner cylindrical member 140 (shown in FIG. 29(b)). It has a relief portion 140d for avoiding interference with the force receiving portion 177.

After the inner cylindrical member 140 is incorporated into the flange member 170, the rotation stopping portion 140c restricts the inner cylindrical member 140 from rotating to the upstream side in the rotational direction, and the retaining portion 140b is disengaged from the cylindrical member pressing portion 178. This is the part to prevent this. It has a snap-fit shape as shown in FIG. 28(B).

(Assembly of coupling members)
As previously mentioned, coupling member 128 consists of flange member 170 and inner cylindrical member 140 . Assembly of the coupling member 128 will be described with reference to FIGS. 29 and 30. FIG.

FIGS. 29(c) and 30(c) respectively show the assembled state of the coupling member 128. FIG.

First, as shown in FIGS. 29(a) and 30(a), the inner cylindrical member 140 is assembled to the flange member 170 from the Z1 side toward the Z2 side. At this time, the inner cylindrical member 140 is assembled at a phase on the upstream side in the rotational direction of the coupling member 128 with respect to the assembled state shown in FIGS. 29(c) and 30(c). In this phase, the relief portion 140d of the retaining portion 140b and the force receiving portion 177 are in phase. Therefore, as shown in FIGS. 29(b) and 30(b), in the Z direction, the retaining portion 140b is the same as the cylindrical member pressing portion 178, which is a gap provided on the inner side of the force receiving portion 177. assembled in position. At this time, the fitting portion 140a of the inner cylindrical member 140 is fitted to the outer periphery of the inverted conical shape 133a of the flange member 170, so that the rotational centers of the flange member 170 and the inner cylindrical member 140 are aligned with high precision. comes out. At this time, the snap-fit-shaped rotation stopper 140c is bent.

After that, as shown in FIGS. 29(c) and 30(c), the inner cylindrical member 140 is rotated downstream in the rotation direction with respect to the flange member 170. As shown in FIG. This rotation enables the backed-up surface 174i of the engaging portion 173 of the inner cylindrical member 140 and the receiving surface 177a of the force receiving portion 177 of the flange member 170 to come into contact with each other. Also, at this time, the bending of the snap-fit-shaped rotation stopper 140c is released, and the mounting of the inner cylindrical member 140 to the flange member 170 is completed.

That is, the inner cylindrical member 140 is restricted from rotating in relation to the flange member 170 . That is, the inner cylindrical member 140 can rotate on the downstream side in the rotation direction within a range until the backed-up surface 174i comes into contact with the receiving surface 177a. On the upstream side in the rotational direction, the inner cylindrical member 140 can rotate within a range until the rotation stopping portion 140 c contacts the flange member 170 .

[Driving Coupling Member by Main Body Drive Shaft]
Transmission of rotational drive from main body drive shaft 101 to coupling member 128 will be described with reference to FIG.

When the drive receiving surface 173a of the coupling member 128 abuts against the main body drive transmission surface 101b, the drive receiving surface 173a receives the load (driving force) F1 and becomes integrated with the drive transmission surface 101b as in the first embodiment. Rotate.

When the driving force F1 is received by the drive receiving surface 173a, the angle J formed by the surface to be backed up 174i and the driving force receiving surface 173a is an acute angle. can be separated. As shown in FIG. 15, the vertical component Fv is transmitted to the backed-up surface 174i of the engaging portion 173 opposite to the drive receiving surface 173a. Since the engaging portion 173 is backed up by the mounting portion 172 via the rib 177e, the engaging portion 173 is hardly deformed downstream in the rotational direction. When the engaging portion 173 receives the vertical component Fh, the contact surface 174h contacts the shaft portion 101f of the main body drive shaft 101, and the engaging portion 173 is backed up.

As a result, the drive receiving surface 73a can be stably brought into contact with the main body drive receiving surface 101a, and the photosensitive drum unit 30 can be pulled into the main body drive shaft 101 toward the bearing portion 101d. Further, even if the load F1 fluctuates, since the engaging portion 73 is backed up as described above, the engaging portion 73 is substantially not deformed. be able to.

<Example 3>
A third embodiment will be described with reference to FIGS. 31 to 34. FIG.

FIG. 31 is a cross-sectional view of the flange member 270 according to this embodiment cut along the center of the rotation axis (the center of the rotation axis).

FIG. 32 is a cross-sectional view of the coupling member 228 and the main body drive shaft 101 according to this embodiment cut along the direction perpendicular to the rotation axis and passing through the base portion 274 .

FIG. 33 is a perspective view of the alignment member 233 according to this embodiment. FIG. 34 is a diagram showing another form of the coupling member 228 according to this embodiment.

Among the elements of this embodiment, those corresponding to the elements described in the previous embodiment are given the same names as the elements of the previous embodiment. Regarding them, the configuration, operation, etc., which are different from the above-described elements will be described in particular detail, and the description of the same points as the above-described elements may be omitted.

Among the elements of this embodiment, the elements substantially equivalent to the elements of the embodiment described above are given the same names and the same reference numerals, and detailed descriptions thereof are omitted. In this embodiment, as shown in FIG. 31, the root-side extending portion 274t is arranged on the downstream side in the rotation direction with respect to the engaging portion 273, and extends from the root portion (fixed end) 274a in the Z2 direction (the axis of the drum unit 30). direction). The root-side extending portion 274 t is arranged substantially parallel to the rotation axis of the flange member 270 . In addition, the folded portion 274r is formed continuously with the root side extension portion 274t, and is also continuously connected to the free end side extension portion 274s.

The free end side extending portion 274s extends along the axial direction from the folded portion 274r toward the Z1 direction (the outer side of the drum unit 30 in the axial direction).

An engaging portion (protruding portion) 273 is formed on the free end side extending portion 274s.

The folded portion 274r is arranged on the far side (Z2 side) of the drum unit 30 in the axial direction with respect to the engaging portion 273. As shown in FIG.

In this embodiment, the free end side extending portion 274s and the base side extending portion 274t are arranged at different positions in the circumferential direction (rotational direction) of the drum unit 30 . In other words, the free end side extension portion 274s and the root side extension portion 274t are arranged at positions shifted from each other in the circumferential direction (rotational direction). In other words, the free end side extension portion 274s is arranged upstream of the root side extension portion 274t in the rotational direction (see FIG. 32). This point is different from the first embodiment.

As in the first embodiment, the support portion for movably supporting the driving force receiving portion (driving receiving surface 273a) is formed by the base portion 274 and the engaging portion 273. FIG.

The alignment member 233 has an inverted conical shape 233a, a fitting portion 233b, a retaining portion 233c, and a backup portion 233j, as in the first embodiment (see FIG. 33). As shown in FIG. 32, the transmission of the driving force F1 when the coupling member 228 is driven by the main body drive shaft 101 is the same as in the first embodiment, and the engaging portion 273 is connected to the mounting portion 272 via the backup portion 233j and the rib 277e. The configuration backed up by is also the same as that of the first embodiment. Also in this embodiment, the alignment member 233 is a backup member and a positioning member.

Further, when the cartridge 1 is attached to the image forming apparatus main body 100, the engaging portion 273 moves radially outward. At this time, the root-side extending portion 274t and the folded portion 274r of the base portion 274 are elastically deformed so that the cartridge 1 can be attached with a low load, as in the first embodiment.

Also, in this embodiment, for the sake of explanation, the root side extending portion 274t is arranged downstream in the rotational direction with respect to the engaging portion 273 and the free end side extending portion 274s. However, the root side extending portion 274t may be arranged on the upstream side in the rotational direction with respect to the engaging portion 273 and the free end side extending portion 274s (see FIG. 34(a)). Alternatively, as shown in FIG. 34(b), the root side extending portion 274t is arranged on both upstream and downstream sides in the rotational direction with respect to the engaging portion 273 and the free end side extending portion 274s. It's okay. At this time, as a matter of course, the folded portions 274r are also arranged on both sides in the rotation direction with respect to the engaging portion 273 and the free end side extending portion 274s.

That is, in the configuration shown in FIG. 34(b), the support portions (273, 274) have two root side extension portions 274t for supporting the free end side extension portions 274s. In other words, the free end side extension portion 274s is connected to the two root side extension portions 274t via the two folded portions 274r. Such support portions (273, 274) are M-shaped (see FIG. 34(b)).

<Example 4>
A fourth embodiment will be described with reference to FIGS. 35 to 41. FIG.

FIG. 35 is a sectional view of the coupling member 328 according to this embodiment cut along the center of the rotation axis (the center of the rotation axis).

FIG. 36 is a view of a flange member 370 according to this embodiment viewed from the outside in the Z direction, and a cross-sectional view. FIG. 37 is a perspective view of an inner cylindrical member 340 according to this embodiment. FIG. 39 is a perspective view of the alignment member 333. FIG. 39 is an explanatory view of assembly of the coupling member 328 according to this embodiment. is a cross-sectional view taken at a position passing through the drive transmission surface 373a in the direction of .

FIG. 41 is a view showing another embodiment of the inner cylindrical member 340 according to this embodiment. Elements corresponding to those described in the previous embodiment are given the same names as in the previous embodiment. attached. Regarding them, the configuration, operation, etc., which are different from the above-described elements will be described in particular detail, and the description of the same points as the above-described elements may be omitted.

Among the elements of this embodiment, the elements substantially equivalent to the elements of the embodiment described above are denoted by the same names and the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, the points different from the third embodiment will be described in detail. Each of the free end side extending portion 374s and the fixed end side extending portion 374t of the present embodiment differs in extending direction from the free end side extending portion 274s and the fixed end side extending portion 274t of the third embodiment. .

In the third embodiment, the coupling member 228 is composed of the flange member 270 and the alignment member 233 , and the flange member 270 has the engaging portion 273 and the base portion 274 . In addition, the base portion 274 has the folded portion 274r arranged on the back side (Z2 side) with respect to the engaging portion.

In contrast, in this embodiment, the coupling member 328 is composed of a flange member 370, an inner cylindrical member 340, and an alignment member 333, as shown in FIG. The inner cylindrical member 340 is a driving force receiving member as in the second embodiment, and the alignment member 333 is a backup member, a transmitted member, and a positioning member as in the second embodiment.

More specifically, the flange member 370 has a mounting portion 372, a cylindrical portion 371, a collar portion 375, and a force receiving portion 377, as shown in FIG.

37, the inner cylindrical member 340 has a base portion 374, an engaging portion 373, and a fitting portion 340a. The base portion 374 has a root extending portion 374t and a folded portion 374r as in the third embodiment.

In this embodiment, as shown in FIG. 37, the root side extending portion 374t is arranged downstream in the rotational direction with respect to the engaging portion 373 and the free end side extending portion 374s. The root-side extending portion 374 t extends from the root portion 374 a in the Z1 direction (outside in the axial direction of the drum unit 30 ) and is arranged substantially parallel to the rotation axis of the flange member 370 . In addition, the folded portion 374r is formed continuously with the root side extension portion 374t and continuously connected with the free end side extension portion 374s.

The folded portion 374r is arranged on the Z1 side with respect to the tip of the free end side extending portion 374s (the free end of the engaging portion 373).

The free end side extending portion 374 s extends in the Z2 direction (inner side in the axial direction of the drum unit 30 ) from the folded portion 374 r and is arranged substantially parallel to the rotational axis of the flange member 370 .

An engaging portion 373 is formed over substantially the entire free end side extending portion 374s. The engaging portion 373 is provided with a drive receiving surface 373a as a driving force receiving portion.

As shown in FIG. 38, the alignment member 333 has an inverted conical shape 333a, an alignment member fitting portion 333i, a retainer portion 333j, and an inner cylindrical member fitted portion 333k.

As shown in FIG. 39, the alignment member fitting portion 333i is fitted to the inner peripheral surface 372m (see FIG. 36) of the mounting portion 372 of the flange member 370. As shown in FIG. As shown in FIG. 38, the retaining portion 333j has a snap-fit shape extending in the Z direction. As shown in FIG. 39, the flange member 370 has a hole shape 372b at a location corresponding to the retaining portion 333j. The inner cylindrical member fitting portion 333k fits with the fitting portion 340a of the inner cylindrical member 340, as shown in FIG.

As shown in FIG. 39, the inner cylindrical member 340 and the alignment member 333 are assembled to the flange member 370 from the Z2 side to the Z1 side to form the coupling member 328 . As shown in FIG. 35, in the assembled state of the coupling 328, the inner cylindrical member 340 is sandwiched between the flange member 370 and the alignment member 333 to restrict movement in the Z direction. The inner cylindrical member 340 is rotatably assembled to the flange member 370 to the extent that the engaging portion 373 abuts against the force receiving portions 377 on the upstream side and the downstream side in the rotational direction.

When the coupling member 328 is driven by the main body drive shaft 101, as shown in FIG. It is backed up in section 372 . Therefore, the engaging portion 373 is hardly deformed downstream in the rotational direction.

Further, as in the first embodiment, when the cartridge 1 is attached to the image forming apparatus main body 100, when the engaging portion 373 moves radially outward, the root side extending portion 374t and the folded portion 374r of the base portion 374 are elastically deformed. By doing so, the cartridge 1 can be mounted with a low load.

Also, in this embodiment, for the sake of explanation, the inner cylindrical member 340 has the root-side extending portion 374t arranged downstream with respect to the engaging portion 373 in the rotational direction. However, the inner cylindrical member 340 may be arranged on the upstream side in the rotational direction as shown in FIG. 41(a) or may be arranged on both sides in the rotational direction as shown in FIG. 41(b).

In the fourth embodiment and the first to third embodiments described above, the configuration of the coupling member for receiving the driving force for driving the photosensitive drum 1 of the drum cartridge 13 has been described.

In other words, each of the coupling members ( 28 , 128 , 228 , 328 ) described above can be provided in the developing cartridge 4 . In this case, each coupling member (28, 128, 228, 328) receives a driving force for driving elements provided in the developing cartridge 4, such as the developing roller 17, the toner supply roller 18, the stirring member 23, and the like. It will be. Examples of such configurations are described in detail in Examples 5 and 6 below.

<Example 5>
A fifth embodiment will be described with reference to FIGS. 42 to 57. FIG.

In this embodiment, the coupling member 528 provided in the developing cartridge 4 for driving the developing roller 17, the toner supply roller 18, and the stirring member 23 of the developing cartridge 4 will be described. Also, the main body drive shaft 5101 provided in the image forming apparatus main body 100A for transmitting the driving force to the coupling member 528 will be described.

In the above-described Embodiments 1 to 4, the structure of the drive connecting portion (coupling member and main body drive shaft 101) between the apparatus main body and the drum cartridge has been explained. In the present embodiment and a sixth embodiment described later, this configuration is applied to the configuration of the drive connecting portion (coupling member 528 and main body drive shaft 5101) between the apparatus main body and the developing cartridge.

Therefore, among the elements of this embodiment, those corresponding to the elements described in the previous embodiment are given the same names as the elements described above. Regarding them, the configuration, operation, etc., which are different from the above-described elements will be described in particular detail, and the description of the same points as the above-described elements may be omitted.

Further, among the elements of this embodiment, the same names and the same reference numerals are given to the elements that are the same as those of the previously described embodiments, and detailed description thereof will be omitted.

[Configuration of main body drive shaft]
The configuration of the main body drive shaft 5101 will be described with reference to FIGS. 42 and 43. FIG.

42 is an outline view of the main body drive shaft 5101. FIG.

FIG. 43 is a cross-sectional view of the main body drive shaft 5101 attached to the image forming apparatus main body, cut along its rotation axis (rotational axis).

As shown in FIG. 42, the main body drive shaft 5101 is composed of a gear member 5101e, an intermediate body 5101p, an output member 5101q, and a drive transmission member 5101r.

The image forming apparatus main body 100A is provided with a motor (not shown) as a drive source. The gear member 5101e receives rotational drive from this motor, and drive is transmitted to the intermediate member 5101p, the output member 5101q, and the drive transmission member 5101r in this order, and the main body drive shaft 5101 rotates.

Further, the gear member 5101e, the intermediate member 5101p, and the output member 5101q have an Oldham's joint mechanism, and can move a certain distance in the X direction and the Y direction. Therefore, the drive transmission member 5101r provided on the cartridge side of the main body drive shaft 5101 through the Oldham's coupling can also move a certain distance in the X direction and the Y direction. The drive transmission member 5101r has a rotatable shaft portion 5101f, and the rotational driving force received from the motor passes through a groove-shaped drive transmission groove 5101a (recessed portion, drive transfer portion) provided in the shaft portion 5101f. It is transmitted to the developing cartridge 4 side. Moreover, the shaft portion 5101f has a conical shape 5101c at its tip.

The main body drive transmission groove 5101a is shaped so that a part of an engaging portion 573, which will be described later, can enter. Specifically, it includes a main body drive transmission surface 5101b as a surface that contacts the drive receiving surface (drive receiving portion) 573a of the coupling member 528 and transmits the driving force.

Further, as shown in FIG. 42, the main body drive transmission surface 5101b is not flat, but has a twisted shape about the rotation axis of the main body drive shaft 5101. As shown in FIG. The twist direction is a direction in which the Z1 direction side of the main body drive shaft 5101 is disposed on the upstream side in the rotation direction of the main body drive shaft 5101 with respect to the Z2 direction side. In this embodiment, the amount of twisting of the engaging portion 573 along the rotation axis direction of the cylinder is set to about 1° per 1 mm. The reason why the body drive transmission surface 5101b has a twisted shape will be described later.

In addition, a body-side withdrawal taper 5101i is provided on the surface of the body drive transmission groove 5101a on the Z2 direction side. The body-side withdrawal taper 5101i is a taper (inclined surface, inclined portion) for helping the engaging portion 573 to come out of the drive transmission groove 5101a when the developing cartridge 4 is removed from the apparatus main body 100A.

As shown in FIG. 43, the bearing portion 5101d provided in the gear member 5101e is rotatably supported (pivotally supported) by a bearing member 5102 provided in the image forming apparatus main body 100A. Next, the output member 5101q is rotatably supported by a coupling holder 5101s. Further, the drive transmission member 5101r is supported by the output member 5101q so as to be movable in the Z direction, and is urged by the spring member 5103 toward the developing cartridge 4 (Z2 direction). However, the movable amount (backlash) of the drive transmission member 5101q in the Z direction is about 1 mm, which is sufficiently smaller than the width of the drive receiving surface 573a described later in the Z direction.

Further, the coupling holder 5101s is biased in the Y2 direction by a biasing spring 5101t, and as will be described later, when the developing cartridge 4 is mounted, the drive transmission member 5101r moves substantially Y2 with respect to the axis of the gear member 5101e. It is in a position shifted in the direction.

As described above, the drive transmission member 5101r is provided with the main body drive transmission groove 5101a, and the coupling member 528 is provided with the engaging portion 573 to transmit the drive from the apparatus main body 100A to the developing cartridge 4. FIG.

Although the details will be described later, the engaging portion 573 is provided at the tip of a base portion 574 that is elastically deformable. Therefore, the engaging portion 573 is configured to be movable radially outward when the developing cartridge 4 is attached to the apparatus main assembly 100A. Accordingly, as the developing cartridge 4 is inserted into the apparatus main body 100A, the engaging portion 573 enters the drive transmission groove 5101a, and the engaging portion 573 can be engaged with the body drive transmission groove 5101a.

The engaging portion 573 has a driving force receiving portion for receiving driving force from the outside of the developing cartridge 4 . As in the above embodiments, the base 574 and the engaging portion form a supporting portion for movably supporting the driving force receiving portion.

[Configuration of Coupling Member]
Next, the coupling member 528 of this embodiment will be described in detail with reference to FIGS. 44, 45, 46, 47, 48 and 49. FIG.
FIG. 44 is a cross-sectional view of the coupling member 528 taken along the axis of rotation.
FIG. 45 is a cross-sectional view of the cylinder member 570 taken along the rotation axis.
FIG. 46 is a cross-sectional view of the coupling member 528 and the main body drive shaft 5101 taken in a direction perpendicular to the rotational axis of the coupling member 528 and passing through the drive receiving surface 573a.
47 is a perspective view of the alignment member 533. FIG.
48A and 48B are diagrams for explaining the assembly of the coupling member 528. FIG.
49 is a cross-sectional view of the developing cartridge 4 cut along the axis of the toner supply roller 20 and developing roller 17. As shown in FIG. made up of the body. However, depending on the selection of material, molding method, configuration, etc., the number of members need not be two, and three or more members may be combined.

The cylinder member 570 is a driving force receiving member provided with a driving force receiving surface 573a for receiving driving force from the apparatus body, as in the first embodiment. The alignment member 533 is a member to which driving force is transmitted from the cylinder member 570, as in the first embodiment. The alignment member 533 is also a backup member provided with a backup portion that suppresses the movement of the drive receiving surface 573 a in the circumferential direction of the cylinder member 570 .

As shown in FIG. 48, the alignment member 533 is attached to the cylinder member 570 in the axial direction (indicated by the arrow) of the cylinder member 570 . Further, by rotating the alignment member 533 counterclockwise (indicated by an arrow), the retaining portion 533c is engaged with the hook portion 572, and the alignment member 533 and the cylinder member 570 are unitized.

(Description on flange member)
As shown in FIG. 45, the cylinder member 570 has an engaging portion 573 and a base portion 574 as in the first embodiment. The engaging portion 573 and the base portion 574 are support portions for movably supporting the driving force receiving portion (driving receiving surface 573a) as in the first embodiment.

As in the first embodiment, as shown in FIG. 46, the engaging portions 573 are arranged at three positions (120° intervals, substantially equal intervals) in the circumferential direction of the coupling member 528. 573a. The base portion 574 has a surface to be backed up 574i and a contact surface 574h.

The drive receiving surface 573 a is a surface that transmits the driving force of the main body drive shaft 5101 to the coupling member 528 by coming into contact with the main body drive transmission surface 5101 b of the main body drive shaft 5101 .
The contact surface 574h is a surface that contacts the shaft portion 5101f when the coupling member 528 is engaged with the main body drive shaft 5101, and the radius R51 of the arc that forms the inner diameter of the contact surface 574h is substantially the same as the radius R52 of the shaft portion 5101f. is.

The backed-up portion 574i is a surface that contacts a receiving surface 577a of the force receiving portion 577 of the alignment member 533, which will be described later, when the coupling member 528 is engaged with the main body drive shaft 5101. It is arranged on the downstream side in the rotational direction (FIG. 46). Further, as shown in FIG. 46, the backed-up surface 574i and the drive receiving surface 573a are arranged so that the angle J forms an acute angle.

Incidentally, the drive receiving surface 573a may have different phases in the rotational direction at the two points in contact with the drive transmission member 5101r. That is, the drive receiving surface 573a does not necessarily have a twisted shape as long as it has a function equivalent to that of a twisted surface. By forming the drive receiving surface 573a into a twisted shape or an inclined shape, when the drive receiving surface 573a receives a drive, the coupling member 528 receives a force that draws the developing cartridge 4 to the outside (Z1 direction side). Join.

Further, as shown in FIG. 45, the engaging portion 573 has an insertion tapered surface 573d as a force receiving portion at the time of attachment on the outer side (Z1 direction side) of the developing cartridge 4 in the Z direction. Further, the engaging portion 573 has a withdrawal tapered surface 573e as a force receiving portion at the time of removal inside the developing cartridge 4 in the Z direction (Z2 direction side). This makes it possible to improve the attachment and detachment of the coupling member 4028 to and from the main body drive shaft 5101 .

At the time of mounting, the insertion tapered surface 573d and the conical shape 5101c abut against each other, and the engaging portion 573 is moved radially outward of the drive shaft. In addition, during withdrawal, the withdrawal taper surface 573e and the main body side withdrawal taper 5101i abut against each other, and the engaging portion 573 is moved radially outward of the main body drive shaft 5101. As shown in FIG.

The base portion 574 has a root side extension portion 574t, a folded portion 574r, and a free end side extension portion 574s, as in the first embodiment. As in the first embodiment, the root-side extending portion 574t extends from the root portion 574a substantially parallel to the rotation axis of the cylinder member 570 in the Z2 direction (inward in the axial direction of the developing roller). The root side extending portion 574t is arranged radially outside the coupling member with respect to the engaging portion 573 and the free end side extending portion 574s.

The folded portion 574r is formed continuously with the root side extending portion 574t, and is a portion that is also continuously connected with the free end side extending portion 574s.

The root-side extending portion 574t extends from the folded portion 574r in the Z1 direction (outside in the axial direction of the developing roller) substantially parallel to the rotational axis of the cylinder member 570. As shown in FIG.

Both the free end of the engaging portion 573 (the tip of the free end side extending portion 574s) and the root 574a of the base portion are arranged on the Z1 side of the folded portion 574r.

The engaging portion 573 is a protrusion provided on the free end side extending portion 574s, and has a driving force receiving portion (driving receiving surface 573a).

As in the first embodiment, elastic deformation of the base portion 574 allows the engaging portion 573 to move in the radial direction of the coupling member 528 . In other words, the base portion 574 deforms when subjected to an external force, and has a restoring force (elastic force) in the direction of returning to its natural position.

As in the first embodiment, when the coupling member 528 is engaged with the main body drive shaft 5101, both the root side extending portion 574t and the folded portion 574r are elastically deformed, so that the coupling member 528 can be attached with a low mounting force. It can be attached to the main body drive shaft 5101 .

The drive receiving surface 573a of the coupling member 528 is twisted about the axis of the coupling member 528, and in this embodiment, the amount of twist is the same as that of the main body drive transmission surface 5101b.

(Description of the alignment member)
Next, as shown in FIG. 47, the alignment member 533 has an inverted conical shape 533a, a force receiving portion 577, a retainer portion 533c, and an alignment member drive transmission surface (hereinafter simply referred to as a drive transmission surface). have.

The inverted conical shape 533a is a portion for determining the axial position and radial position of the main body drive shaft 5101 . The drive transmission member 5101r is restricted from moving in the axial direction and radial direction of the main body drive shaft 5101 by contacting the drive transmission member 5101r with the drive transmission member 5101r.

The force receiving surface 577 consists of a receiving surface 577a (see FIG. 46) that abuts against a backed-up surface 574i provided on the engaging portion 573 in the assembled state of the coupling 528, and a rib perpendicular to the receiving surface 577a. 577e (see FIG. 46). The receiving surface 577 a is a backup portion and a transmitted portion for receiving driving force from the cylinder member 570 as in the first embodiment.

As shown in FIG. 48, the drive transmission surface 533m is a surface (transmitted portion) to which drive is transmitted from the cylinder member 570 to the alignment member 533. As shown in FIG. The cylinder member 570 has a corresponding cylinder drive transmission surface (drive transmission portion) 570m. They are arranged at three locations (120° intervals, substantially equal intervals) in the circumferential direction of the alignment member 533 and the cylinder member 570, respectively.

The cylinder drive transmission surface 570m and the drive transmission surface 533m are twisted along the axes of the cylinder member 570 and the alignment member 453, respectively, and the amount of twist is about 2° per 1 mm.

The following relationship holds for the amount of twist. The cylinder member 570 receives a force Fz1 that draws the developer cartridge 4 to the outside (Z1 direction side) at the drive receiving surface 573a. In addition, the cylinder member 570 receives a force Fz2 that draws the developer cartridge 4 inward (Z2 direction side) at the flange drive transmission surface 570m. In this case, the relationship is always Fz2>Fz1.

Therefore, the cylinder member 570 is always pulled in the Z2 direction. In addition, at least a portion of the engagement portion D in the Z direction between the cylinder drive transmission surface 570m and the drive transmission surface 33m overlaps the drive receiving surface 573a and the receiving surface 577a of the force receiving portion 577 in the Z direction. is. This makes it possible to suppress the amount of deformation of the cylinder member 570 .

In this embodiment, an attachment portion 533d (see FIG. 37), which is a D-shaped hole provided in the alignment member 533, is attached to the shaft of the toner supply roller 20 as shown in FIG. When the drive is transmitted from the alignment member 533 to the shaft of the toner supply roller 20, the toner supply roller 20 becomes rotatable. Next, the drive is transmitted to the toner supply roller gear 598 provided on the Z1 direction side of the axis of the toner supply roller 20 . Finally, the driving force is transmitted from the toner supply roller gear 598 to the developing roller gear 599 provided on the Z1 direction side of the axis of the developing roller 17, so that the developing roller 17 is rotatable. Both ends of the developing roller 17 are rotatably supported by developing bearings 519R and 519L.

[Attachment of Cartridge to Image Forming Apparatus]
Attachment/detachment of the developing cartridge 4 to/from the image forming apparatus main body 100A will be described with reference to FIGS. 50 and 51. FIG.

FIG. 50 is a perspective view for explaining how the developing cartridge 4 is attached to the image forming apparatus main body 100A.

FIG. 51 is a sectional view for explaining the mounting operation of the developing cartridge 4 to the image forming apparatus main body 100A.

The image forming apparatus main body 100A of this embodiment employs a configuration in which the developing cartridge 4 can be horizontally mounted. Specifically, the image forming apparatus main body 100A has a space in which the developing cartridge 4 can be mounted. A cartridge door 5104 (front door) for inserting the developing cartridge 4 into the aforementioned space is provided on the front side of the image forming apparatus main body 100A (the direction in which the user stands during use).

As shown in FIG. 50, the cartridge door 5104 of the image forming apparatus main body 100A is openable. When the cartridge door 5104 is opened, a cartridge lower guide rail 5105 for guiding the developing cartridge 4 is arranged on the bottom surface of the space, and a cartridge upper guide rail 5106 is arranged on the upper surface. The developing cartridge 4 is guided to the mounting position by upper and lower guide rails (5105, 5106) provided above and below the space. The developing cartridge 4 is inserted into the mounting position substantially along the axis of the developing roller 20 .

The attachment/detachment operation of the developing cartridge 4 to/from the image forming apparatus main body 100A will be described below with reference to FIG.

As shown in FIG. 51( a ), the developing cartridge 4 is supported and guided by the cartridge lower guide rail 5105 at the lower end of the developing cartridge 4 on the far side in the insertion direction. The developing cartridge 4 is guided by an upper cartridge guide rail 5106 (not shown) at the upper end on the far side in the insertion direction. In this state, the developing cartridge 4 is inserted into the apparatus main body. At this time, the development frame 18 and the development bearings 19 (19L, 19R) are dimensionally related so that the intermediate transfer belt 5 does not come into contact with them.

Next, as shown in FIG. 51(b), the developing cartridge 4 is horizontally inserted while being supported by the cartridge lower guide rail 5105, and is inserted into the far side cartridge positioning portion 5108 provided in the image forming apparatus main body 100A. It is inserted until it hits.

Further, when the developing cartridge 4 is mounted, the drive transmission member 5101r of the image forming apparatus main body 100A is engaged with the coupling member 528 while being biased substantially in the Y2 direction, as described above.

FIG. 51C is a diagram showing the state of the image forming apparatus main body 100A and the developing cartridge 4 with the cartridge door 5104 closed. A cartridge lower guide rail 5105 of the image forming apparatus main body 100A is configured to move up and down in conjunction with opening and closing of a cartridge door (front door) 5104 .

When the cartridge door 5104 is closed by the user, the cartridge lower guide rail 5105 is raised. Both ends of the developing cartridge 4 abut on the cartridge positioning portions (5108 and 5110) of the image forming apparatus main body 100A, and the developing cartridge 4 is positioned with respect to the image forming apparatus main body 100A. Further, the drive transmission member 5101r of the image forming apparatus main body 100A also follows the developing cartridge 4 and rises.

By the above operation, the mounting of the developing cartridge 4 to the image forming apparatus main body 100A is completed.

Further, the removal of the developing cartridge 4 from the image forming apparatus main body 100A is performed in the reverse order of the insertion operation described above.

[Process of Engaging Coupling Member with Main Body Drive Shaft]
Next, the engagement process between the coupling member 528 and the main body drive shaft 5101 will be described in detail with reference to FIG.

52 is a cross-sectional view for explaining the mounting operation of the coupling member 528 to the main body drive shaft 5101. FIG.

FIG. 52(a) is a diagram showing a state before the coupling member 528 starts engaging with the drive transmission member 5101r. FIG. 52(d) shows a state in which the developing cartridge 4 is attached to the image forming apparatus main body 100A. In particular, FIG. 52D shows a state in which the cartridge lower guide rail 105 is lifted as the cartridge door 5104 is closed, and the developing cartridge 4 is positioned with respect to the image forming apparatus main body 100A.

Here, FIGS. 52(b) and 52(c) are diagrams for explaining the mounting process of the coupling member 528 and the drive transmission member 5101r between FIGS. 52(a) and 52(d). The drive transmission member 5101r is biased substantially in the Y2 direction by a biasing spring 5101t, and the axis of the drive transmission member 5101r is biased to a position shifted substantially in the Y2 direction from the axis of the coupling member 528.

As described with reference to FIG. 51, the developing cartridge 4 is horizontally inserted while being supported by the cartridge lower guide rail 5105 of the image forming apparatus main body 100A.

FIG. 52(a) is a diagram showing a state in which the drive transmission member 5101r is not in contact with the coupling member 528. FIG. As described above, in this state, the axis of the drive transmission member 5101r and the axis of the coupling member 528 are out of alignment.

As shown in FIG. 52(b), when the coupling member 528 is further inserted into the drive transmission member 5101r from FIG. The conical shape 5101c of 5101r abuts. The tapered insertion surface 573d of the coupling member 528 guides the conical shape 5101c of the drive transmission member 5101r, so that the axis of the coupling member 528 and the axis of the drive transmission member 5101r are substantially the same.

As shown in FIG. 52(c), FIG. 52(c) is a diagram showing a state in which the coupling member 528 is further inserted toward the inner side of the drive transmission member 5101r from FIG. 52(b). By elastically deforming the base portion 574, the engaging portion 573 is deformed radially outward of the coupling member 528 so that the insertion taper 573d of the engaging portion 573 follows the conical shape 5101c. Further, when the coupling member 528 is inserted in the Z1 direction, the withdrawing tapered surface 573e of the engaging portion 573 of the coupling member 528 moves toward the inner side in the Z direction (Z1 side) from the main body side withdrawing taper 5101i of the drive transmission member 5101r. It is inserted into the drive transmission member 5101r until it comes. Next, the coupling member 528 is inserted into the drive transmission member 5101r until the positioning portion 533a of the coupling member 528 and the conical shape 5101c of the drive transmission member 5101r contact each other.

After that, as described above, the developing cartridge 4 is lifted by the cartridge lower guide rail 5105, so that the developing cartridge 4 is positioned with respect to the image forming apparatus main body 100A (FIG. 51(c)). Further, as shown in FIG. 51(d), as the developing cartridge 4 rises, the drive transmission member 5101r also rises. After that, as in the first embodiment, when the main body drive shaft 5101 rotates and the phases of the engaging portion 573 and the drive transmission groove 5101a match, the elastic deformation of the base portion 574 is released, and the engaging portion 573 is engaged in the drive transmission. It penetrates into the groove 5101a.

[Driving Coupling Member by Main Body Drive Shaft]
Rotational drive transmission from main body drive shaft 5101 to coupling member 528 will be described with reference to FIG.

When the drive receiving surface 573a of the coupling 528 abuts against the main body drive transmission surface 5101b, the developing roller 17, the developing blade 21 and the like apply a load via the developing roller 17. As shown in FIG. That is, the drive receiving surface 573a rotates integrally with the drive transmission surface 101b while receiving the load (driving force) F51.

When the driving force F51 is received by the drive receiving surface 753a, the angle J formed by the surface to be backed up 574i and the driving force receiving surface 573a is an acute angle. can be separated. As shown in FIG. 46, the vertical component Fv is transmitted to the backed-up surface 574i of the engaging portion 573 opposite to the drive receiving surface 573a. The backed-up surface 574i hits the force receiving surface 577a and is backed up by the rib 577e perpendicular to the force receiving surface 577a. As a result, even if the load F51 fluctuates, since the engagement portion 573 is backed up as described above, it is substantially not deformed. , the image quality can be preserved.

Further, the removal of the developing cartridge 4 from the image forming apparatus main body 100A is performed in the reverse order of the insertion operation described above.

In this embodiment, the root-side extending portion 574t extends to the far side (Z2 direction) substantially parallel to the rotation axis of the cylinder member 570. As shown in FIG. The root-side extending portion 574t is arranged radially outward of the engaging portion 573, and both the free end side of the engaging portion 573 and the root 574a of the base portion are arranged on the Z1 side of the folded portion 574r.

As another embodiment, as shown in FIG. 53, both the free end side of the engaging portion 573 and the root 574a of the base portion may be arranged on the Z2 side of the folded portion 574r.

As shown in FIGS. 54(a) and 55, the root-side extending portion 574t may be arranged on the downstream side in the rotational direction with respect to the engaging portion 573, and may extend to the far side (Z2 direction) from the root portion 274a. good. As shown in FIG. 54(b), the root side extending portion 574t may be arranged on the upstream side in the rotational direction with respect to the engaging portion 573 and may extend to the back side (Z2 direction) from the root portion 274a. As shown in FIG. 54(c). The root-side extending portion 574t may be arranged on both sides of the engaging portion 573 in the rotational direction.

As shown in FIGS. 56(a) and 57, the root-side extending portion 574t is arranged downstream in the rotational direction with respect to the engaging portion 573 and the free-end-side extending portion 574s, and extends from the root portion 574a in the Z1 direction. It may be configured to extend to. As shown in FIG. 56(b), the root side extending portion 574t is arranged on the upstream side in the rotational direction with respect to the engaging portion 573 and the free end side extending portion 574s, and extends from the root portion 574a in the Z1 direction. Configuration is fine. As shown in FIG. 56(c), the root side extending portion 574t may be arranged on both sides in the rotational direction with respect to the engaging portion 573 and the free end side extending portion 574s.

<Example 6>
A sixth embodiment will be described with reference to FIGS. 58 to 63. FIG.

FIG. 58 is a perspective view of the alignment member 633 according to this embodiment.

FIG. 59 is a cross-sectional view of the alignment member 633 according to this embodiment cut along the rotation axis.

FIG. 60 is a cross-sectional view of the coupling member 628 according to this embodiment, cut along the drive receiving surface 673a in the direction perpendicular to the rotation axis.

FIG. 61 is a perspective view of a cylinder member 670 according to this embodiment.

FIG. 62 is a cross-sectional view of the coupling member 628 according to this embodiment taken along the rotation axis.

FIG. 63 is a diagram illustrating assembly of the coupling member 628 according to this embodiment.

Elements corresponding to those disclosed in the previous embodiments are given the same names. Regarding them, the configuration, operation, etc., which are different from the above-described elements will be described in particular detail, and the description of the same points as the above-described elements may be omitted. Elements that are substantially the same as those described above are given the same names and reference numerals, and detailed descriptions thereof are omitted. In this embodiment, the points different from the fifth embodiment will be described in detail.

In the fifth embodiment, a cylinder member 570 and an alignment member 533 constitute a coupling member 528, the cylinder member 570 has a cylinder drive transmission surface 570m, a base portion 574, and an engaging portion 573. It is configured to have a receiving portion 577 and a drive transmission surface 533m.

On the other hand, in this embodiment, the cylinder member 670 is provided with a backup portion 670j, and the alignment member 633 is provided with a base portion 674, an engaging portion 673, and a force receiving portion 677. FIG.

More specifically, as shown in FIG. 58, the alignment member 633 has a base portion 674, an engaging portion 673, a force receiving portion 677, an inverted conical shape 633a, and a retaining portion 633c.

As shown in FIG. 59, the base portion 674 has a root portion 674a on the Z1 side, a root side extension portion 674t extending in the axial direction of the coupling member 628, a free end side extension portion 674s, and a root side extension portion 674s. It has an existing portion 674t and a folded portion 674r.

The engaging portion 673 has a drive receiving surface 673a as in the fifth embodiment. That is, the alignment member 633 is a driving force receiving member provided with a driving force receiving portion for receiving the driving force from the apparatus main body.

In addition, the free end side extending portion 674s has a surface to be backed up 674i and a contact surface 674h.

The angle j formed by the drive receiving surface 673a and the backed-up surface 674i is an acute angle as in the fifth embodiment.

As shown in FIG. 60, the force receiving portion 677 is arranged downstream of the engaging portion 673 in the rotational direction, and has a receiving surface 677a and ribs 677e. The receiving surface 677a is a surface for sandwiching a backup portion 670j of the cylinder member 670, which will be described later, with a surface 674i of the base portion 674 to be backed up. The receiving surface 677a and the backed-up surface 674i are arranged substantially parallel. As shown in FIG. 60, the rib 677e is arranged substantially perpendicular to the receiving surface 677a starting from the inner diameter side end of the receiving surface 677a.

Also, the inverted conical shape 633a is a portion for determining the positions of the coupling member 628 and the main body drive shaft 5101, as in the fifth embodiment.

The retaining portion 633 c is a portion that unitizes the alignment member 633 and the cylinder member 670 by engaging with a hook portion 672 provided on the cylinder member 670 .

The cylinder member 670 has a backup portion 670j and a hook portion 672, as shown in FIG. That is, the cylinder member 670 is a backup member having a backup portion.

As shown in FIG. 60, the backup portion 670j is assembled in the gap between the backed-up surface 674i of the alignment member 633 and the receiving surface 677a, and has a shape that prevents the engaging portion 673 from tilting toward the upstream side in the rotational direction. be. Therefore, the thickness of the backup portion 670j is set substantially equal to the gap between the surface to be backed up 674i and the receiving surface 677a. Also, when viewed from the Z direction, a circle passing through the ridgeline of the backup portion 670j on the engaging portion 673 side is arranged so that its center is the same as the inverted conical shape 633a. The diameter D68 of the circle is approximately the same as the outer diameter D65 of the shaft portion 5101f of the main body drive shaft 5101, or is created so that D68≧D65 when the respective dimensional accuracies are considered. Also, as shown in FIG. 62, the backup portion 670j is arranged so as to overlap the drive receiving surface 673a in the Z direction.

A coupling member 628 is formed by assembling the alignment member 633 to the cylinder member 670 from the back side in the Z direction to the front side (from the Z2 side to the Z1 side) (see FIG. 62). At this time, the retaining portion 633c of the alignment member 633 engages with the hook portion 672 provided on the cylinder member 670, as described above.

When the coupling member 628 receives drive from the main body drive shaft 5101, as shown in FIG. 60, the drive receiving surface 673a of the engaging portion 673 receives the drive force F1. Among them, the force Fv in the direction perpendicular to the backed-up surface is backed up by the backed-up surface 674i, the backup portion 670j, the receiving surface 670a, and the rib 670e. can be prevented. In addition, against the force Fh in the direction parallel to the backed-up surface 674i, the contact surface 674h of the base portion 674 abuts against the shaft portion 5101f of the main body drive shaft 5101, so that the engaging portion 673 is deformed in the radial direction. can be prevented.

Further, in Example 5, the cylinder member 570 is provided with the engaging portion 573, and the alignment member 533 is arranged so as to straddle the inverted conical shape 533a and another component. Therefore, the cylinder member 570 is provided with a cylinder drive transmission surface 570m, and the alignment member 533 is provided with a drive transmission surface 533m. By pulling the cylinder member 570 toward the alignment member 533 side (Z2 direction side), the positions of the engaging portion 573 and the inverted conical shape 533a in the Z direction are stabilized.

On the other hand, in this embodiment, since the engaging portion 673 and the inverted conical shape 633a are arranged on the alignment member 633, it is not necessary to pull the cylinder member 670 toward the alignment member 633 side.

As another embodiment, similarly to FIG. 53 of Embodiment 5, the root portion 674a of the root side extension portion 674t of the base portion 674 is provided on the Z2 side, and the folded portion 674r is provided on the Z1 side of the root side extension portion 674t. (not shown). 54 and 56, the root side extending portion 674t may be arranged on the upstream side, downstream side, or both sides of the engaging portion 673 in the rotational direction. The configurations of Examples 1 to 6 described above are summarized as follows. According to each configuration described in the present application, the support portion that supports the driving force receiving portion (driving receiving surface) has the first extension portion and the second extension portion that extend in mutually different directions, so that it is possible to Even if the support part can secure a certain length. That is, the supporting portion can movably support the driving force receiving portion while keeping the size of the coupling and the cartridge small. Further, with such a configuration of the support portion, when the cartridge is mounted in the image forming apparatus main body, the driving force receiving portion (engagement portion) can engage with the main body drive shaft provided in the image forming apparatus main body.

According to the present invention, there is provided a photosensitive drum unit that is detachably attached to an electrophotographic image forming apparatus main body.

Claims (28)

in the drum unit
a photoreceptor drum;
A coupling member capable of transmitting a driving force toward the photosensitive drum, comprising: (i) a main body having a cylindrical shape ; (ii) a projection movable with respect to the main body; and (iii) the projection. (iv) a second extension connected to the inner surface of said body; and (v) said first extension between said first and second extensions. a coupling member having a connecting portion connecting the portion and the second extending portion;
has
The first extension is connected to the main body via the second extension,
A first direction in which the first extension portion extends from the connection portion and a second direction in which the second extension portion extends toward the connection portion are opposite to each other in an axial direction of the coupling member,
The drum unit, wherein the protrusion protrudes from the first extending portion so as to approach the axis of the coupling member. 2. A drum unit according to claim 1 , wherein said protrusion is movable in the radial direction of said coupling member . At least one of the first extension portion and the second extension portion is elastically deformable, and the projection is movable by elastic deformation of at least one of the first extension portion and the second extension portion. 3. A drum unit according to claim 1 or 2 . 4. A drum unit according to any one of claims 1 to 3 , wherein said connecting portion is a bent portion. 5. A drum unit according to claim 1 , wherein said first extension is located closer to said axis of said coupling member than said second extension is. 6. The drum unit according to any one of claims 1 to 5 , wherein the first extending portion and the second extending portion are displaced from each other in the circumferential direction of the coupling member. 7. The coupling member according to any one of claims 1 to 6 , wherein the coupling member has a plurality of second extensions, and the first extension is connected to the plurality of second extensions. drum unit. 8. The drum unit of claim 7 , wherein the first extension and the plurality of second extensions form an M shape. 9. The drum unit according to any one of claims 1 to 8 , wherein the coupling member has a backup portion that prevents the projection from moving with respect to the main body. 10. The drum unit according to any one of claims 1 to 9 , wherein at least part of said first extending portion is arranged inside said photosensitive drum. 10. The drum unit according to any one of claims 1 to 9 , wherein at least a part of said projection is arranged inside said photosensitive drum. 12. The drum unit according to any one of claims 1 to 11 , wherein the coupling member is configured to transmit the driving force from the projection toward the photosensitive drum. a drum unit according to any one of claims 1 to 12 ;
a frame that rotatably supports the drum unit;
cartridge. in the cartridge,
a rotating body configured to carry toner on its outer peripheral surface;
A coupling member capable of transmitting a driving force toward the rotating body, comprising: (i) a body having a cylindrical shape ; (ii) a projection movable with respect to the body; and (iii) supporting the projection. (iv) a second extension connected to the inner surface of the body; and (v) the first extension between the first extension and the second extension. and a connection portion connecting the second extension portion;
has
The first extension is connected to the main body via the second extension,
A first direction in which the first extension portion extends from the connection portion and a second direction in which the second extension portion extends toward the connection portion are opposite to each other in an axial direction of the coupling member,
The protrusion protrudes from the first extending portion so as to approach the axis of the coupling member. 15. A cartridge according to claim 14 , wherein said protrusion is movable in the radial direction of said coupling member . At least one of the first extension portion and the second extension portion is elastically deformable, and the projection is movable by elastic deformation of at least one of the first extension portion and the second extension portion. 16. A cartridge according to any one of claims 14 or 15 . 17. A cartridge according to any one of claims 14 to 16 , wherein said connecting portion is a bent portion. 18. A cartridge according to any one of claims 14 to 17 , wherein said first extension is located closer to said axis of said coupling member than said second extension is. 19. A cartridge according to any one of claims 14 to 18 , wherein said first extending portion and said second extending portion are displaced from each other in the circumferential direction of said coupling member. 20. The coupling member according to any one of claims 14 to 19 , wherein the coupling member has a plurality of second extensions, and the first extension is connected to the plurality of second extensions. cartridge. 21. A cartridge according to claim 20 , wherein said first extension and said plurality of second extensions form an M shape. 22. A cartridge according to any one of claims 14 to 21 , wherein said coupling member has a backup portion for restraining movement of said protrusion with respect to said main body. 23. A cartridge according to any one of claims 14 to 22 , wherein said rotating body is a photosensitive drum. 24. The cartridge according to claim 23 , wherein at least a part of said first extending portion is arranged inside said photosensitive drum. 25. A cartridge according to Claim 23 or 24 , wherein at least a portion of said projection is arranged inside said photosensitive drum. 23. A cartridge according to any one of claims 14 to 22 , wherein said rotating body is a developing roller. 27. The apparatus according to claim 26 , further comprising a supply roller configured to supply toner to said developing roller, wherein said developing roller is configured to receive driving force from said coupling member via said supply roller. cartridge. 28. A cartridge according to any one of claims 14 to 27 , wherein said coupling member is configured to be able to transmit said driving force from said projection toward said rotor .

Images